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Sample records for autogenous bone dust

  1. Guided bone regeneration using autogenous tooth bone graft in implant therapy: case series.

    Science.gov (United States)

    Kim, Young-Kyun; Kim, Su-Gwan; Bae, Ji-Hyun; Um, In-Woong; Oh, Ji-Su; Jeong, Kyung-In

    2014-04-01

    Recently, techniques have been reported that involve the preparation of extracted teeth from patients used as particulated bone graft materials for bone graft purposes. For implant placement and bone graft, autogenous teeth bone graft materials were used in 15 patients, and clinically excellent results were obtained. In histological examination, favorable bony healing by osteoconduction was observed.

  2. A new view on bone graft in dental implantation: Autogenous bone mixed with titanium granules

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    Yeke Wu

    2013-01-01

    Full Text Available Introduction : Dental implants have been widely applied in clinic for many years. However, the success rate is still challenging mainly because of bone deficiency. An ideal bone graft is traditionally thought to guide and induce new bone regeneration as well as been absorbed completely by human body. The Hypothesis: Autogenous bone mixed with titanium granules might be an ideal bone graft for dental implantation. Evaluation of the Hypothesis: First, we analyzed advantages of grafts of autogenous bone mixed with titanium granules, such as serving as a s scaffold for wound healing and tissue regeneration, creating sui microenvironment for implant-bone integration, shortening the new bone′s creeping distance, etc. Then we creatively hypothesized a novel alternative bone graft with premixed autogenous bone and non-absorbent titanium granules. Apart from repairing bone deficiency, our hypothesis could promote the integration between new bone and titanium implant from the perspective of microenvironment. We believe that the method is promising and worth extension in clinical application.

  3. Bone-to-implant contact after maxillary sinus floor augmentation with Bio-Oss and autogenous bone in different ratios in mini pigs

    DEFF Research Database (Denmark)

    Jensen, Thomas; Schou, Søren; Gundersen, Hans Jørgen G;

    2012-01-01

    OBJECTIVES: The objective was to test the hypotheses: (i) no differences in bone-to-implant contact formation, and (ii) no differences between the use of autogenous mandibular or iliac bone grafts, when autogenous bone, Bio-Oss mixed with autogenous bone, or Bio-Oss is used as graft for the maxil...

  4. Sinusfloor elevation and grafting with autogenous iliac crest bone.

    Science.gov (United States)

    van den Bergh, J P; ten Bruggenkate, C M; Krekeler, G; Tuinzing, D B

    1998-12-01

    Insufficient bone height in the posterior area of the maxilla, due to expansion of the maxillary sinus and atrophic reduction of the alveolar process of the maxilla, represents a contra-indication for insertion of dental implants. This anatomic problem can, in many cases, be solved by augmentation of the floor of the maxillary sinus. This surgical technique was introduced by Tatum. The so-called top hinge door method creates a new floor of the maxillary sinus at a more cranial level. Underneath this new floor the existing space is filled with a bone graft. Implantation in the alveolar process with increased bone height allows insertion of dental implants. This sinus grafting technique was used in the present study. In total, 62 sinusfloor elevations were performed with cancellous iliac bone grafts in 42 patients. In those 62 augmented sinuses, 161 ITI screw type implants were inserted. The follow-up was 1-6 years after implantation. In 2 cases infections occurred. One implant needed an extended integration time. No implants were lost. The ITI solid screw implant appears to be a suitable implant following sinusfloor elevation operations, due to its rough surface, its shape and the size of the thread. The sinusfloor elevation procedure with autogenous cancellous bone graft appears to be a valuable and reliable pre-implantological procedure, provided a proper pre-operative investigation and careful surgery are performed. This procedure allows dental implant placement with a high success rate.

  5. Bone formation by autogenous grafting of cultured bone/porous ceramic constructs in a dog

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

    2001-07-01

    Five ml of bone marrow was collected from the humerus of a 6 month old female dog by needle aspiration. The marrow was cultured in T-75 flask and expand the marrow mesenchymal cells. After 1 week in primary culture, cells were released by trypsin treatment, concentrated and loaded onto porous hydroxyapatite (HA) blocks. The marrow/HA constructs were subcultured in the presence of dexamethasone and beta-glycerophosphate (osteogenic medium). After 2 weeks of subculture, the autogenous cultured bone/HA constructs were subcutaneously implanted into the back of the dog. Histological findings of the constructs at 3 weeks after implantation revealed thick layer of lamellar bone together with active osteoblasts lining in many pore areas of the HA. High alkaline phosphatase activity could be detected in the construct. These results indicate that autogenous cultured bone/HA constructs can produce extensive bone formation after implantation in a large animal(dog). Therefore, based upon the fact that human marrow-derived culture bone/HA construct possesses osteogenic potential when it is grafted into nude mice, it can be expected that autogenous human cultured bone/ceramic grafts may be useful to reconstruct bone in the clinical setting. (orig.)

  6. Bone Formation in Maxillary Sinus Lift Using Autogenous Bone Graft at 2 and 6 Months

    Science.gov (United States)

    Netto, Henrique Duque; Miranda Chaves, Maria das Graças Alfonso; Aatrstrup, Beatriz; Guerra, Renata; Olate, Sergio

    2016-01-01

    SUMMARY The aim of this study is to compare the bone formation in maxillary sinus lift with an autogenous bone graft in histological evaluation at 2 or 6 months. A comparative study was designed where 10 patients with missing teeth bilaterally in the posterior zone of the maxilla were selected. Patients received a particulate autogenous bone graft under the same surgical conditions, selecting a site to collect a biopsy and histological study at two months and another at six months postoperatively. Histomorphometry was performed and were used Kolmogorov-Smirnov test, student’s t-test and Spearman’s correlation coefficient, considering a value of p<0.05. Differences were observed in inflammatory infiltrate and vascularization characteristics; however, the group analyzed at two months presented 38.12% ± 6.64 % of mineralized tissue, whereas the group studied at 6 months presented an average of 38.45 ± 9.27 %. There were no statistical differences between the groups. It is concluded that the bone formation may be similar in intrasinus particulate autogenous bone grafts in evaluations at two or six months; under these conditions, early installation of implants is viable. PMID:27867255

  7. Histomorphometric evaluation of bone regeneration using autogenous bone and beta-tricalcium phosphate in diabetic rabbits

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    Živadinović Milka

    2016-01-01

    Full Text Available Background/Aim. The mechanism of impaired bone healing in diabetes mellitus includes different tissue and cellular level activities due to micro- and macrovascular changes. As a chronic metabolic disease with vascular complications, diabetes affects a process of bone regeneration as well. The therapeutic approach in bone regeneration is based on the use of osteoinductive autogenous grafts as well as osteoconductive synthetic material, like a β-tricalcium phosphate. The aim of the study was to determine the quality and quantity of new bone formation after the use of autogenous bone and β-tricalcium phosphate in the model of calvarial critical-sized defect in rabbits with induced diabetes mellitus type I. Methods. The study included eight 4-month-old Chincilla rabbits with alloxan-induced diabetes mellitus type I. In all animals, there were surgically created two calvarial bilateral defects (diameter 12 mm, which were grafted with autogenous bone and β-tricalcium phosphate (n = 4 or served as unfilled controls (n = 4. After 4 weeks of healing, animals were sacrificed and calvarial bone blocks were taken for histologic and histomorphometric analysis. Beside descriptive histologic evaluation, the percentage of new bone formation, connective tissue and residual graft were calculated. All parameters were statistically evaluated by Friedman Test and post hock Wilcoxon Singed Ranks Test with a significance of p < 0.05. Results. Histology revealed active new bone formation peripherally with centrally located connective tissue, newly formed woven bone and well incorporated residual grafts in all treated defects. Control samples showed no bone bridging of defects. There was a significantly more new bone in autogeonous graft (53% compared with β-tricalcium phosphate (30%, (p < 0.030 and control (7%, (p < 0.000 groups. A significant difference was also recorded between β-tricalcium phosphate and control groups (p < 0.008. Conclusion. In the present

  8. Physicochemical Characteristics of Bone Substitutes Used in Oral Surgery in Comparison to Autogenous Bone

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    Antoine Berberi

    2014-01-01

    Full Text Available Bone substitutes used in oral surgery include allografts, xenografts, and synthetic materials that are frequently used to compensate bone loss or to reinforce repaired bone, but little is currently known about their physicochemical characteristics. The aim of this study was to evaluate a number of physical and chemical properties in a variety of granulated mineral-based biomaterials used in dentistry and to compare them with those of autogenous bone. Autogenous bone and eight commercial biomaterials of human, bovine, and synthetic origins were studied by high-resolution X-ray diffraction, atomic absorption spectrometry, and laser diffraction to determine their chemical composition, calcium release concentration, crystallinity, and granulation size. The highest calcium release concentration was 24. 94 mg/g for Puros and the lowest one was 2.83 mg/g for Ingenios β-TCP compared to 20.15 mg/g for natural bone. The range of particles sizes, in terms of median size D50, varied between 1.32 μm for BioOss and 902.41 μm for OsteoSponge, compared to 282.1 μm for natural bone. All samples displayed a similar hexagonal shape as bone, except Ingenios β-TCP, Macrobone, and OsteoSponge, which showed rhomboid and triclinic shapes, respectively. Commercial bone substitutes significantly differ in terms of calcium concentration, particle size, and crystallinity, which may affect their in vivo performance.

  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. Repair process of surgical defects filled with autogenous bone grafts in tibiae of diabetic rats

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    Jônatas Caldeira Esteves

    2008-10-01

    Full Text Available From a biological standpoint, the best material for reconstruction of bone defects is the autogenous bone graft. However, as tissue healing is affected under diabetic conditions, major changes might take place in the revascularization, incorporation, replacement and remodeling phases of the grafted area. The purpose of this study was to assess the bone healing process in surgical wounds prepared in tibiae of diabetic rats and filled with autogenous bone. Forty male rats (Rattus norvegicus albinus, Wistar were randomly assigned to receive an endovenous injection (penile vein of either citrate buffer solution (Group 1 - control; n=20 or streptozotocin dissolved in citrate buffer solution (35 mg/kg to induce diabetes (Group 2 - diabetic; n=20. After determination of glycemia, the animals were anesthetized and the anterolateral regions of the tibiae of both limbs were shaved, antisepsis was performed and longitudinal incisions were made in each limb. The tibiae were exposed and two 2mm-diameter surgical cavities were prepared: one in the right limb, filled with particulate autogenous bone and the other in the left limb, filled with blood clot. The animals were euthanized at 10 and 30 postoperative days. The anatomic pieces were obtained, submitted to laboratory processing and sections were stained by hematoxylin and eosin and Masson's Trichrome for histomorphologic and histometric analyses. In both groups, the wounds filled with autogenous bone graft showed better results than those filled with blood clot. The control group showed higher new bone formation in wounds filled with autogenous bone graft at 30 days than the diabetic group, but without statistical significance. It may be concluded that, in general, the new bone formation occurred with autogenous graft was quantitatively similar between control and diabetic groups and qualitatively better in the control group.

  11. Alternative method to treat oroantral communication and fistula with autogenous bone graft and platelet rich firbin

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    Niedzielska, Iwona; Borgiel-Marek, Halina; Różanowski, Bartosz

    2016-01-01

    Background Removing a tooth from the jaw results in the occurrence of oroantral communication in beneficial anatomic conditions or in the case of a iatrogenic effect. Popularized treatments of the oroantral communication have numerous faults. Large bone defect eliminates the chance to introduce an implant. Purpose of this work was assessment of the usefulness of autogenous bone graft and PRF in normal bone regeneration in the site of oroantral communication. Material and Methods Bone regeneration in the site of oroantral communication was assessed in 20 patients. Bone defects were supplemented autogenous bone graft from mental protuberance in 14 cases and from oblique line in 6 cases. The graft was covered with a PRF membrane. Results In the study group in all cases closure of the oroantral communication was observed. The average width of the alveolar was 13 mm and the average height was 12.5 mm. In 3 patients an average increase of alveolar height of 1.5 mm was observed. Conclusions This method may be the best option to prepare alveolar for new implant and prosthetic solutions. Key words:Oroantral communication, oroantral fistula, autogenous bone graft, bone regeneration, platelet rich fibrin. PMID:27475687

  12. Histological evaluation of healing after transalveolar maxillary sinus augmentation with bioglass and autogenous bone

    DEFF Research Database (Denmark)

    Stavropoulos, Andreas; Sima, Catalin; Sima, Andrea;

    2012-01-01

    OBJECTIVES: The aim was to evaluate histologically the outcome of a bioglass and autogenous bone (at 1 : 1 ratio) composite implantation for transalveolar sinus augmentation. METHODS: In 31 patients, during implant installation ca. 4 months after sinus augmentation, biopsies were harvested throug...

  13. Augmentation of localized defects of the anterior maxillary ridge with autogenous bone before insertion of implants

    NARCIS (Netherlands)

    Raghoebar, GM; Batenburg, RHK; Vissink, A; Reintsema, H

    1996-01-01

    Purpose: This study evaluated the applicability of intraorally harvested autogenous bone grafts for the augmentation of the narrow maxillary alveolar ridge to enable insertion of implants for single tooth replacement. Materials and Methods: Local defects of the anterior maxilla were reconstructed in

  14. Maxillary sinus floor elevation surgery with BioOss (R) mixed with a bone marrow concentrate or autogenous bone : test of principle on implant survival and clinical performance

    NARCIS (Netherlands)

    Rickert, D.; Vissink, A.; Slot, Jan; Sauerbier, S.; Meijer, H. J. A.; Raghoebar, G. M.

    2014-01-01

    The purpose of this study was to assess implant survival and 1-year clinical performance of implants placed in the posterior maxilla that had been subjected to maxillary sinus floor elevation surgery with bovine bone mineral (BioOss (R)) mixed with autogenous bone marrow concentrate or autogenous bo

  15. Augmentation of the rat jaw with autogeneic cortico-cancellous bone grafts and guided tissue regeneration.

    Science.gov (United States)

    Donos, Nikolaos; Kostopoulos, Lambros; Karring, Thorkild

    2002-04-01

    The aim of the present study was to evaluate the effect of augmenting the maxillary alveolar ridge and the lateral aspect of the mandible with onlay autogeneic cortico-cancellous bone grafts that were covered with e-PTFE membranes. The experiment was carried out in 51 rats. In 15 rats, the edentulous maxillary jaw between the incisor and the first molar was augmented by means of an autogeneic ischiac bone graft that was fixed with a gold-coated microimplant. In one side, the graft was covered with an e-PTFE membrane, while the other side, which served as control, was treated without a membrane. In the other 36 rats, the lateral aspect of the mandible was augmented in both sides by means of an autogeneic ischiac bone graft that was fixed with a gold-coated or a titanium microimplant. In one side, the augmented area was covered with an e-PTFE membrane, while the contralateral side was treated without a membrane. Histological analysis at 60, 120 and 180 days after augmentation of the maxilla showed that, in the case of the test sites (where most of the membranes were either exposed or lost), the bone grafts presented extensive resorption and there was a lack of bone continuity between the graft and the recipient site. Similar findings were made at the non-membrane-treated control sides. In the case of augmentation of the mandible with membranes, the bone grafts were not resorbed, but were integrated into newly formed bone at the recipient site. In the control sides, the grafts presented varying degrees of resorption and integration into the recipient bone. It is concluded that, in comparison to bone grafting alone, onlay ischiac bone grafting combined with guided tissue regeneration eliminates the risk of bone graft resorption and ensures integration of the graft into newly formed bone at the recipient site, provided that closure of the operated area can be maintained during healing.

  16. Reconstruction of the mandible with a poly(D,L-lactide) scaffold, autogenous corticocancellous bone graft, and autogenous platelet-rich plasma: an animal experiment.

    NARCIS (Netherlands)

    Fennis, J.P.M.; Stoelinga, P.J.W.; Merkx, M.A.T.; Jansen, J.A.

    2005-01-01

    An animal study is presented, evaluating a method of mandibular reconstruction using a poly(D,Llactide) (PDLLA) scaffold. Six goats underwent a continuity resection of the mandibular angle. The defect was bridged with a preshaped PDLLA scaffold, filled with an autogenous particulate bone graft from

  17. Autogenous bone block in the treatment of teeth with hopeless prognosis

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    Nymphea Pandit

    2012-01-01

    Full Text Available Background: Autogenous bone graft, although considered as a gold standard, has been relegated to background because of limited quantity and donor site morbidity. Revival of interest in its use has been reflected by its tremendous capacity for regeneration in less than ideal situation. Bone blocks have been used for implant site augmentation, with varied success. Aim: Aim of the study was to evaluate the efficacy of autogenous bone block in the regeneration of bone, for saving teeth with a hopeless prognosis. Settings and Design: A total of six patients and 12 sites with grade II and III mobile teeth were treated with autogenous bone blocks and fiber splinting. Subjects and Methods: Attachment loss, probing depths, and radiographic bone loss were recorded at baseline and at 12 months interval. Statistical Analysis Used: The Student paired t test was used for evaluation of the changes from baseline to 12 months. Results: At 12 months post-operatively, there was a highly significant amount of bone gain as compared to the baseline. The mean amount of bone loss reduced from 9.41 ± 1.16 to 5.41 ± 1.01. The clinical attachment loss reduced from 7.37 ± 1.24 mm to 3.79 ± 0.89 mm and probing depth reduced from 7 ± 1.67 mm to 5.5 ± 0.63 mm. The grafted bone was observed to have been incorporated with the host bone in most of the sites as evidenced by radiographs. Conclusions: For teeth with hopeless prognosis, this method can be considered to be a very viable alternative to extraction and replacement by costly implants.

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

    DEFF Research Database (Denmark)

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

    2003-01-01

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

  19. Autogenous bone graft combined with polylactic polyglycolic acid polymer for treatment of dehiscence around immediate dental implants.

    Science.gov (United States)

    Hassan, Khalid S

    2009-11-01

    The use of composite bone grafts in dehiscence defects around immediate dental implants are aimed at improving the outcome of the regenerative process. The present study was designed to evaluate the efficacy of combinations of autogenous bone graft with a synthetic copolymer polylactic and polyglycolic acid (Fisiograft) on bone healing of buccal dehiscence defects around immediate dental implants. Sixteen adult male patients who each received an immediate implant for a single tooth replacement at a maxillary anterior or premolar site were included in this study. Patients were divided into 2 groups. One group received immediate dental implants augmented with autogenous bone graft combined with Fisiograft. The other group received immediate dental implants augmented with autogenous bone graft alone. The results revealed that both treatment modalities led to significant improvements for the primary outcome regarding bone fill as well as a significant reduction of probing pocket depth and gain of attachment level. Moreover, there were slightly statistically significant differences between the groups. In conclusion, the combination of autogenous bone graft and Fisiograft showed a slight superiority to autogenous bone graft alone, suggesting that it could be an optimum bone substitute for treatment of dehiscence around immediate dental implant.

  20. Evaluation of ABM/P-15 versus autogenous bone in an ovine lumbar interbody fusion model.

    Science.gov (United States)

    Sherman, Blake P; Lindley, Emily M; Turner, A Simon; Seim, Howard B; Benedict, James; Burger, Evalina L; Patel, Vikas V

    2010-12-01

    A prospective, randomized study was performed in an ovine model to compare the efficacy of an anorganic bovine-derived hydroxyapatite matrix combined with a synthetic 15 amino acid residue (ABM/P-15) in facilitating lumbar interbody fusion when compared with autogenous bone harvested from the iliac crest. P-15 is a biomimetic to the cell-binding site of Type-I collagen for bone-forming cells. When combined with ABM, it creates the necessary scaffold to initiate cell invasion, binding, and subsequent osteogenesis. In this study, six adult ewes underwent anterior-lateral interbody fusion at L3/L4 and L4/L5 using PEEK interbody rings filled with autogenous bone at one level and ABM/P-15 at the other level and no additional instrumentation. Clinical CT scans were obtained at 3 and 6 months; micro-CT scans and histomorphometry analyses were performed after euthanization at 6 months. Clinical CT scan analysis showed that all autograft and ABM/P-15 treated levels had radiographically fused outside of the rings at the 3-month study time point. Although the clinical CT scans of the autograft treatment group showed significantly better fusion within the PEEK rings than ABM/P-15 at 3 months, micro-CT scans, clinical CT scans, and histomorphometric analyses showed there were no statistical differences between the two treatment groups at 6 months. Thus, ABM/P-15 was as successful as autogenous bone graft in producing lumbar spinal fusion in an ovine model, and it should be further evaluated in clinical studies.

  1. Histological evaluation of the influence of magnetic field application in autogenous bone grafts in rats

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    Ponzoni Deise

    2009-01-01

    Full Text Available Abstract Background Bone grafts are widely used in oral and maxillofacial reconstruction. The influence of electromagnetic fields and magnets on the endogenous stimulation of target tissues has been investigated. This work aimed to assess the quality of bone healing in surgical cavities filled with autogenous bone grafts, under the influence of a permanent magnetic field produced by in vivo buried devices. Methods Metal devices consisting of commercially pure martensitic stainless steel washers and titanium screws were employed. Thirty male Wistar rats were divided into 3 experimental and 3 control groups. A surgical bone cavity was produced on the right femur, and a bone graft was collected and placed in each hole. Two metallic washers, magnetized in the experimental group but not in the control group, were attached on the borders of the cavity. Results The animals were sacrificed on postoperative days 15, 45 and 60. The histological analysis of control and experimental samples showed adequate integration of the bone grafts, with intense bone neoformation. On days 45 and 60, a continued influence of the magnetic field on the surgical cavity and on the bone graft was observed in samples from the experimental group. Conclusion The results showed intense bone neoformation in the experimental group as compared to control animals. The intense extra-cortical bone neoformation observed suggests that the osteoconductor condition of the graft may be more susceptible to stimulation, when submitted to a magnetic field.

  2. Pure orbital blowout fractures reconstructed with autogenous bone grafts: functional and aesthetic outcomes.

    Science.gov (United States)

    Kronig, S A J; van der Mooren, R J G; Strabbing, E M; Stam, L H M; Tan, J A S L; de Jongh, E; van der Wal, K G H; Paridaens, D; Koudstaal, M J

    2016-04-01

    The purpose of this study was to investigate the ophthalmic clinical findings following surgical reconstruction with autogenous bone grafts of pure blowout fractures. A retrospective review of 211 patients who underwent surgical repair of an orbital fracture between October 1996 and December 2013 was performed. Following data analysis, 60 patients who were followed up over a period of 1 year were included. A solitary floor fracture was present in 38 patients and a floor and a medial wall fracture in 22 patients. Comparing preoperative findings between these two groups, preoperative diplopia and enophthalmos were almost twice as frequent in the group with additional medial wall fractures: diplopia 8% and 14% and enophthalmos 18% and 55%, respectively. One year following surgery there was no diplopia present in either group. In the solitary floor fracture group, 3% still had enophthalmos. It can be concluded that at 1 year following the repair of pure orbital floor fractures using autogenous bone, good functional and aesthetic results can be obtained. In the group with both floor and medial wall fractures, no enophthalmos was found when both walls were reconstructed. When the medial wall was left unoperated, 29% of patients still suffered from enophthalmos after 1 year.

  3. Full-thickness tissue engineered skin constructed with autogenic bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    HE LiJuan; PEI XueTao; NAN Xue; WANG YunFang; GUAN LiDong; BAI CiXian; SHI ShuangShuang; YUAN HongFeng; CHEN Lin; LIU DaQing

    2007-01-01

    To explore the feasibility of repairing clinical cutaneous deficiency, autogenic bone marrow mesenchymal stem cells (BMSCs) were isolated and differentiated into epidermal cells and fibroblasts in vitro supplemented with different inducing factors and biomaterials to construct functional tissueengineered skin. The results showed that after 72 h induction, BMSCs displayed morphologic changes such as typical epidermal cell arrangement, from spindle shape to round or oval; tonofibrils, melanosomes and keratohyaline granules were observed under a transmission electronic microscope. The differentiated cells expressed epidermal stem cell surface marker CK19 (59.66%±4.2%) and epidermal cells differentiation marker CK10. In addition, the induced epidermal cells acquired the anti-radiation capacity featured by lowered apoptosis following exposure to UVB. On the other hand, the collagen microfibrils deposition was noticed under a transmission electronic microscope after differentiating into dermis fibroblasts; RT-PCR identified collagen type Ⅰ mRNA expression in differentiated cells;radioimmunoassay detected the secretion of interleukin-6 (IL-6) and interleukin-8 (IL-8) (up to 115.06pg/mL and 0.84 ng/mL, respectively). Further in vivo implanting BMSCs with scaffold material shortened skin wound repair significantly. In one word, autogenic BMSCs have the potential to differentiate into epidermal cells and fibroblasts in vitro, and show clinical feasibility acting as epidermis-like and dermis-like seed cells in skin engineering.

  4. Full-thickness tissue engineered skin constructed with autogenic bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    To explore the feasibility of repairing clinical cutaneous deficiency, autogenic bone marrow mesen-chymal stem cells (BMSCs) were isolated and differentiated into epidermal cells and fibroblasts in vitro supplemented with different inducing factors and biomaterials to construct functional tissue- engineered skin. The results showed that after 72 h induction, BMSCs displayed morphologic changes such as typical epidermal cell arrangement, from spindle shape to round or oval; tonofibrils, melano-somes and keratohyaline granules were observed under a transmission electronic microscope. The differentiated cells expressed epidermal stem cell surface marker CK19 (59.66% ± 4.2%) and epidermal cells differentiation marker CK10. In addition, the induced epidermal cells acquired the anti-radiation capacity featured by lowered apoptosis following exposure to UVB. On the other hand, the collagen microfibrils deposition was noticed under a transmission electronic microscope after differentiating into dermis fibroblasts; RT-PCR identified collagen type I mRNA expression in differentiated cells; radioimmunoassay detected the secretion of interleukin-6 (IL-6) and interleukin-8 (IL-8) (up to 115.06 pg/mL and 0.84 ng/mL, respectively). Further in vivo implanting BMSCs with scaffold material short-ened skin wound repair significantly. In one word, autogenic BMSCs have the potential to differentiate into epidermal cells and fibroblasts in vitro, and show clinical feasibility acting as epidermis-like and dermis-like seed cells in skin engineering.

  5. Supplementation of autogenous bone graft with coralline hydroxyapatite in posterior spine fusion for idiopathic adolescent scoliosis.

    Science.gov (United States)

    Mashoof, A Allen; Siddiqui, Saqib A; Otero, Marilyn; Tucci, James J

    2002-10-01

    Twenty-seven consecutive patients with adolescent idiopathic scoliosis underwent posterior spinal fusion with pediatric Texas Scottish Rite Hospital instrumentation. Coralline hydroxyapatite (Interpore, Irvine, Calif) was mixed with limited autograft from posterior iliac crest (an approximate 70/30 ratio of coralline hydroxyapatite to autograft). Patient evaluation was based on clinical and radiographic findings. On initial radiographic evaluation, a "snowstorm" appearance consistent with the exoskeleton of the coralline hydroxyapatite was observed. After two years, the fusion mass had a "marble-like" appearance with distinct decreased visibility of the disk spaces in the fusion mass. This latter stage of "marbilization correlated with solid fusion clinically. All patients achieved solid fusion at an average follow-up of 27 months. Coralline hydroxyapatite is safe, biocompatible, and effective in augmenting autogenous bone graft in the treatment of idiopathic adolescent scoliosis with posterior spinal fusion. In addition to decreased donor site morbidity, this may be invaluable in cases where there is insufficient autograft available.

  6. The RANK/ RANKL/ OPG interaction in the repair of autogenous bone grafts in female rats with estrogen deficiency

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    Tábata de Mello TERA

    2014-01-01

    Full Text Available The aim of this study was to evaluate the resorption process during the repair of autogenous bone grafts with or without coverage by an expanded polytetrafluoroethylene (e-PTFE membrane in female rats with estrogen deficiency using the immunohistochemical technique. Eighty female rats were randomly divided into two groups (OVX and SHAM. The 40 female rats in the OVX group were subjected to ovariectomy, and the 40 female rats in the SHAM group were subjected to simulated ovariectomy. The two groups were further divided in subgroup E, which was subjected to surgery for placement of autogenous bone graft (ABG, and subgroup ME, in which the ABG was covered with an e-PTFE membrane. The animals were killed at 0, 7, 21, 45 and 60 days. The specimens were analyzed using immunohistochemistry for the bone resorption markers RANK, RANK-L and Osteoprotegerin (OPG. A higher remodeling rate was observed at 7 and 21 days after the autogenous bone grafts, when the markers were more intensely expressed. At the final time point, the specimens presented similar characteristics to those observed at the initial time point. The expression of immunohistochemical markers was not altered by the estrogen deficiency. The presence of the e-PTFE membrane delayed the bone resorption process, influencing the immunohistochemical expression of markers.

  7. Morphology of autogenous bone graft and castor oil polyurethane in the infraorbital rim of rabbits: a comparative study

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    Mendonça José Carlos Garcia de

    2006-01-01

    Full Text Available PURPOSE: Morphological study comparing castor oil polyurethane and autogenous bone graft to repair bone defect in zygomatic bone of rabbits. METHODS: Twenty-four adult, male New Zealand rabbits were randomly distributed between two groups of twelve. Bone defects of 5mm in diameter were cut through the zygomatic bone and filled with polyurethane discs in the experimental group or autogenous bone harvested from the tibia in the control group. Animals were sacrificed after 30, 60 or 90 days, and the zygomatic bones were macro- and microscopically analyzed. Student's, Fisher's, chi-squared and McNemar's tests were used for statistical analysis. RESULTS: Both the castor oil polyurethane and the autograft adapted well to the defect, with no need for fixation. Fibrous connective tissue encapsulated the polyurethane, but no inflammation or giant cell reaction was observed. Acidophilic and basophilic areas were observed inside the micropores of the polyurethane, suggesting cell nuclei. After 90 days, bone repair with a lamellar pattern of organization was observed in the control group. CONCLUSION: The castor oil polyurethane was biocompatible and did not cause inflammation. It may be considered an alternative to fill bone defects.

  8. Rehabilitation of atrophic maxilla using the combination of autogenous and allogeneic bone grafts followed by protocol-type prosthesis.

    Science.gov (United States)

    Margonar, Rogério; dos Santos, Pâmela Letícia; Queiroz, Thallita Pereira; Marcantonio, Elcio

    2010-11-01

    Currently, there are several techniques for the rehabilitation of atrophic maxillary ridges in literature. The grafting procedure using autogenous bone is considered ideal by many researchers, as it shows osteogenic capability and causes no antigenic reaction. However, this type of bone graft has some shortcomings, mainly the restricted availability of donor sites. In recent years, several alternatives have been investigated to supply the disadvantages of autogenous bone grafts. In such studies, allogeneic bone grafts, which are obtained from individuals with different genetic load, but from the same species, have been extensively used. They can be indicated in cases of arthroplasty, surgical knee reconstruction, large bone defects, and in oral and maxillofacial reconstruction. Besides showing great applicability and biocompatibility, this type of bone is available in unlimited quantities. On the other hand, allogeneic bone may have the disadvantage of transmitting infectious diseases. Atrophic maxillae can be treated with bone grafts followed by osseointegrated implants to obtain aesthetic and functional oral rehabilitation. This study aimed to show the viability of allogeneic bone grafting in an atrophic maxilla, followed by oral rehabilitation with dental implant and protocol-type prosthesis within a 3-year follow-up period by means of a clinical case report.

  9. Maxillary sinus lift with solely autogenous bone compared to a combination of autogenous bone and growth factors or (solely) bone substitutes. A systematic review : a systematic review

    NARCIS (Netherlands)

    Rickert, D.; Slater, J. J. R. Huddleston; Meijer, H. J. A.; Vissink, A.; Raghoebar, G. M.

    2012-01-01

    Literature regarding the outcome of maxillary sinus floor elevation to create sufficient bone fraction to enable implant placement was systematically reviewed. Bone fraction and implant survival rate were assessed to determine whether grafting material or applied growth factor affected bone fraction

  10. Long-term results of the use of autogenous cortical bone columellas to replace the stapes at stapedectomy.

    Science.gov (United States)

    Bauer, Miklós; Pytel, József; Vóna, Ida; Gerlinger, Imre

    2011-05-01

    The first author has been using an autogenous cortical bone columella to replace the stapes removed during stapedectomy since 1965. The audiograms of 21 of the 271 patients operated on with this method between 1965 and 1989 (i.e. 7.7% of the possible candidates) were available 20-35 (average 26.8) years postoperatively. The operation could be regarded as successful in 20 and unsuccessful in 1 patient in the long run. The audiological data are presented individually as averages of the values obtained at 0.5, 1, 2 and 3 kHz. The averaged data (n = 21): preoperative air conduction, 58.27; bone conduction, 24.46; and air-bone gap, 33.81 dB. Postoperative best air conduction, 19.07; bone conduction, 14.10; and air-bone gap, 4.97 dB. Postoperative recent air conduction, 45.77; bone conduction, 38.45; and air-bone gap, 7.32 dB. The best values were measured 1-8 (average 1.57) years postoperatively. In relation to the postoperative best value, the recent value of the air-bone gap had deteriorated by 2.35 dB, and that of the bone conduction by 24.35 dB. The small air-bone gap indicates that the deterioration of the hearing is mainly caused by the deterioration of the function of the inner ear and not by that of the conductive apparatus. The progression of the deterioration differs individually (0.3-1.6, average 0.93 dB/year) and accelerates with age. This finding seems to be a problem that does not depend on the operative technique. The data show that the autogenous bone columella ensures the same good and lasting results as the alloplastic solutions; moreover, there is no problem with the incus-prosthesis connection.

  11. Reconstruction of maxillary ridge atrophy caused by dentoalveolar trauma, using autogenous block bone graft harvested from chin: a case report

    Directory of Open Access Journals (Sweden)

    Francisley Ávila Souza

    2014-06-01

    Full Text Available Background: Dentoalveolar trauma, especially when involving front teeth, negatively affect the patient’s life; in particular, tooth avulsion is a complex injury that affects multiple tissues, and no treatment option offers stable long-term outcomes. The aim of this study was to report a case of reconstruction of atrophic anterior alveolar ridge after tooth loss, performed with autograft harvested from the chin, and subsequent prosthetic rehabilitation with the use of an osseointegrated implant. Case report: A 23-years-old Caucasian girl, presented an atrophic alveolar bone in the area of tooth 11, as a result of tooth resorption 10 years after a tooth reimplantation procedure. Reconstruction was performed with autogenous bone harvested from the chin. After 6-months healing period to allow autograft incorporation, a dental implant was inserted. After further 6- months, a screw-retained implant supported metal-ceramic prosthesis was fabricated. Results The prosthetic rehabilitation was successful, and after a follow-up period of 5 years, the achieved result was stable. Conclusion: It can be concluded that the autogenous bone graft harvested from the chin, is a safe and effective option for alveolar ridge defects reconstruction, allowing a subsequent placement of a dental implant supporting a prosthetic restoration.

  12. The Effect of Locally Administered Pamidronate on Autogenous Bone Graft in Maxillofacial Reconstruction: A Randomized Clinical Trial

    Science.gov (United States)

    Bayat, M.; Garajei, A.; Afshari Pour, E.; Hasheminasab, M.; Ghorbani, Y.; Kalantar Motamedi, M. H.; Bahrami, N.

    2017-01-01

    Background: Although bone grafts are commonly used in reconstructive surgeries, they are sensitive to local perfusion and are thus prone to severe resorption. Biphosphonates can inactivate osteoclasts and can be used to control the undesirable bone resorption. Objective: To assess the effect of administration of biphosphonates on bone resorption. Methods: 20 patients with bony defects who were candidates for free autogenous grafts were randomized into “pamidronate” and “control” groups. Bone segments were soaked in either pamidronate solution or normal saline and were inserted into the area of the surgery. Bone densities were measured post-surgery and in 6-month follow-up. Data were obtained via Digora software and analyzed. Results: The mean±SD bone density in pamidronate group changed from 93.4±14.6 to 93.6±17.5 (p<0.05); in the control group the density decreased from 89.7±13.2 to 78.9±11.4 (p<0.05). The mean difference of bone density in anterior areas of the jaws showed higher DXA in comparison to posterior regions (p=0.002). Conclusion: Locally administered pamidronate affects reduction in bone resorption.

  13. Augmentation of the maxillary sinus floor with autogenous bone for the placement of endosseous implants: a preliminary report.

    Science.gov (United States)

    Raghoebar, G M; Brouwer, T J; Reintsema, H; Van Oort, R P

    1993-11-01

    Placement of endosseous implants in the atrophic maxilla is often restricted because of lack of supporting bone. In this article, experience with augmentation of the maxillary sinus floor with autogenous bone grafts to enable insertion of endosseous implants is described. The technique is aimed at providing a cortical layer on top of the graft to ensure a reliable seal of the maxillary sinus and to achieve optimal stability of the bone graft in case of simultaneously placement of dental implants. The procedure was used in 25 patients, using iliac crest grafts (22 patients, 86 implants), symphyseal bone grafts (two patients, six implants), or a maxillary tuberosity bone graft (one patient, one implant). Ninety-three Brånemark implants (Nobelpharma, Götenburg, Sweden) were inserted in 47 grafted maxillary sinuses. The mean follow-up was 16 months (range, 6 to 36 months). No inflammation of the bone grafts nor of the maxillary sinus occurred. The sinus membrane was perforated accidentally in eight cases during the surgical procedure. Five implants (5.4%), all inserted in iliac crest grafts, were lost during the healing period. The patients received implant supported overdentures (16 patients) or bone-anchored bridges (nine patients). From this preliminary study it is concluded that augmentation of the maxillary sinus floor with bone grafts for the insertion of endosseous implants is a promising solution for patients with atrophic maxillae and functional problems with their partial or full dentures.

  14. Maxillary sinus floor augmentation with Bio-Oss or Bio-Oss mixed with autogenous bone as graft in animals: a systematic review

    DEFF Research Database (Denmark)

    Jensen, Thomas; Schou, S; Stavropoulos, A

    2012-01-01

    The objective of the present systematic review was to test the hypothesis of no differences between the use of Bio-Oss or Bio-Oss mixed with autogenous bone as graft for maxillary sinus floor augmentation (MSFA) applying the lateral window technique, as evaluated in animals. A MEDLINE (PubMed...

  15. Maxillary sinus floor augmentation with Bio-Oss or Bio-Oss mixed with autogenous bone as graft: a systematic review

    DEFF Research Database (Denmark)

    Jensen, Thomas; Schou, Søren; Stavropoulos, Andreas;

    2012-01-01

    Aims: The objective of the present systematic review was to test the hypothesis of no differences in the implant treatment outcome when Bio-Oss or Bio-Oss mixed with autogenous bone is used as graft for the maxillary sinus floor augmentation (MSFA) applying the lateral window technique. Material ...

  16. Reconstruction of the mandible using preshaped 2.3 mm titanium plates, autogenous particulate cortico-cancellous bone grafts and platelet rich plasma: a report on eight patients.

    NARCIS (Netherlands)

    Merkx, M.A.W.; Fennis, J.P.M.; Verhagen, C.M.; Stoelinga, P.J.W.

    2004-01-01

    The results are presented of eight patients who had partial mandibulectomies for malignant tumours and were secondarily reconstructed with pre-shaped 2.3 mm titanium plates, autogenous particulate cortico-cancellous bone grafts and platelet rich plasma. Healing was uneventful in all cases and when p

  17. Platelet-rich plasma and autogenous bone graft combined with guided tissue regeneration in periodontal fenestration defects in dogs.

    Science.gov (United States)

    Keskiner, Ilker; Alkan, Arzu; Acikgoz, Gokhan; Arpak, Nejat; Kaplan, Suleyman; Arslan, Huseyin

    2014-01-01

    The aim of this study was to evaluate the effects of platelet-rich plasma (PRP), autogenous bone (AB), and guided tissue regeneration (GTR) combination therapy compared to GTR therapy alone on healing of bone and cementum in fenestration-type periodontal defects in dogs. Six dogs were included in this study. Fenestration-type defects were created, and the following treatment groups were established: a control group treated with GTR alone and experimental groups treated with a combination of GTR + PRP, GTR + AB, and GTR + AB + PRP. The defects were evaluated by stereologic method and histomorphometric analysis, which were performed 4, 8, and 12 weeks postoperatively. The results showed a significant increase in trabecular bone area in the GTR + PRP group as compared with the control at 4 and 8 weeks (P < .05). The GTR + AB + PRP group showed significantly more trabecular bone area than both GTR and GTR + PRP groups at all time intervals (P < .05). The 8- and 12-week results in terms of cementum area revealed a significant difference between the GTR + AB + PRP group and the control in favor of the former (P < .05). Cementum area in the GTR + AB group was significantly greater than that in the GTR group at all time intervals (P < .05). Within the limitations of this study, PRP and AB, when used under barrier membrane, resulted in significant improvement in bone and cementum formation compared to GTR alone in periodontal fenestration defects; AB, rather than PRP, was responsible for this outcome.

  18. Histomorhological and clinical evaluation of maxillary alveolar ridge reconstruction after craniofacial trauma by applying combination of allogeneic and autogenous bone graft.

    Science.gov (United States)

    De Ponte, Francesco Saverio; Falzea, Roberto; Runci, Michele; Siniscalchi, Enrico Nastro; Lauritano, Floriana; Bramanti, Ennio; Cervino, Gabriele; Cicciu, Marco

    2017-02-01

    A variety of techniques and materials for the rehabilitation and reconstruction of traumatized maxillary ridges prior to dental implants placement have been described in literature. Autogenous bone grafting is considered ideal by many researchers and it still remains the most predictable and documented method. The aim of this report is to underline the effectiveness of using allogeneic bone graft for managing maxillofacial trauma. A case of a 30-year-old male with severely atrophic maxillary ridge as a consequence of complex craniofacial injury is presented here. Augmentation procedure in two stages was performed using allogeneic and autogenous bone grafts in different areas of the osseous defect. Four months after grafting, during the implants placement surgery, samples of both sectors were withdrawn and submitted to histological evaluation. On the examination of the specimens, treated by hematoxylin and eosin staining, the morphology of integrated allogeneic bone grafts was revealed to be similar to the autologous bone. Our clinical experience shows how the allogeneic bone graft presented normal bone tissue architecture and is highly vascularized, and it can be used for reconstruction of severe trauma of the maxilla.

  19. Histomorhological and clinical evaluation of maxillary alveolar ridge reconstruction after craniofacial trauma by applying combination of allogeneic and autogenous bone graft

    Directory of Open Access Journals (Sweden)

    Francesco Saverio De Ponte

    2017-02-01

    Full Text Available A variety of techniques and materials for the rehabilitation and reconstruction of traumatized maxillary ridges prior to dental implants placement have been described in literature. Autogenous bone grafting is considered ideal by many researchers and it still remains the most predictable and documented method. The aim of this report is to underline the effectiveness of using allogeneic bone graft for managing maxillofacial trauma. A case of a 30-year-old male with severely atrophic maxillary ridge as a consequence of complex craniofacial injury is presented here. Augmentation procedure in two stages was performed using allogeneic and autogenous bone grafts in different areas of the osseous defect. Four months after grafting, during the implants placement surgery, samples of both sectors were withdrawn and submitted to histological evaluation. On the examination of the specimens, treated by hematoxylin and eosin staining, the morphology of integrated allogeneic bone grafts was revealed to be similar to the autologous bone. Our clinical experience shows how the allogeneic bone graft presented normal bone tissue architecture and is highly vascularized, and it can be used for reconstruction of severe trauma of the maxilla.

  20. Correlation between Density and Resorption of Fresh-Frozen and Autogenous Bone Grafts

    Directory of Open Access Journals (Sweden)

    Simone Lumetti

    2014-01-01

    Full Text Available Trial Design. This analysis compared the outcome of fresh-frozen versus autologous bone block grafts for horizontal ridge augmentation in patients with Cawood and Howell class IV atrophies. Methods. Seventeen patients received autologous grafts and 21 patients received fresh-frozen bone grafts. Patients underwent CT scans 1 week and 6 months after surgery for graft volume and density analysis. Results. Two autologous and 3 fresh-frozen grafts failed. Autologous and fresh-frozen grafts lost, respectively, 28% and 46% of their initial volume (P=0.028. It is noteworthy that less dense fresh-frozen blocks lost more volume than denser grafts (61% versus 16%. Conclusions. According to these 6-month results, only denser fresh-frozen bone graft may be an acceptable alternative to autologous bone for horizontal ridge augmentation. Further studies are needed to investigate its behaviour at longer time points.

  1. Reconstruction of mandibular defects using nonvascularized autogenous bone graft in Nigerians

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    Kizito Chioma Ndukwe

    2014-01-01

    Full Text Available Objectives: The aim of this study is to evaluate the success rate and complications of mandibular reconstruction with nonvascularized bone graft in Ile-Ife, Nigeria. Patients and Methods: A total of 25 patients who underwent reconstruction of mandibular discontinuity defects between January 2003 and February 2012, at the Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife constituted the study sample. Relevant information was retrieved from the patients′ records. This information include patients′ demographics (age and sex as well as the type of mandibular defect, cause of the defect, type of mandibular resection done, source of the bone graft used, and the method of graft immobilization. Morbidity associated with the graft procedures were assessed by retrieving information on graft failures, length of hospital stay following surgery, rehabilitation device used and associated graft donor and recipient site complications. Result: There were 12 males and 13 females with a male:female ratio was 1:1.1. The age of the patients ranged from 13 to 73 years with a mean age for males 32.7 ± standard deviation (SD 12.9 and for females 35.0 ± SD 17.1. Jaw defect was caused by resection for tumours and other jaw pathologies in 92% of cases. Complete symphyseal involvement defect was the most common defect recorded 11 (44%. Reconstruction with nonvascularized rib graft accounted for 68% of cases while iliac crest graft was used in 32% of the patients. Successful take of the grafts was recorded in 22 patients while three cases failed. Wound dehiscence (two patients and postoperative wound infection (eight patients were the most common complications recorded. Conclusion: The use of nonvascularized graft is still relevant in the reconstruction of large mandibular defects caused by surgical ablation of benign conditions in Nigerians. Precise surgical planning and execution, extended antibiotic therapy, and meticulous postoperative care

  2. Comparative clinical and radiographic evaluation of mineralized cancellous bone allograft (puros®) and autogenous bone in the treatment of human periodontal intraosseous defects: 6-months follow-up study

    Science.gov (United States)

    Reddy, B. Ravinder; Sudhakar, J.; Rajesh, Nichenametla; Sandeep, V.; Reddy, Y. Muralidhar; Gnana Sagar, W. R.

    2016-01-01

    Aims: Several materials have been introduced as bone grafts, i.e., autografts, allograft, xenografts, and alloplastic grafts, and studies have shown them to produce greater clinical bone defect fill than open flap debridement alone. The aim of this clinical and radiological 6-month study was to compare and evaluate the clinical outcome of deep intraosseous defects following reconstructive surgery with the use of mineralized cancellous bone allograft (Puros®) or autogenous bone. Materials and Methods: Ten patients with 12 sites exhibiting signs of moderate generalized chronic periodontitis were enrolled in the study. The investigations were confined to two and three-walled intra bony defects with a preoperative probing depth of ≥5 mm. Six of these defects were treated with Puros® (group A) the remaining six were treated with autogenous bone graft (group B). Allocation to the two groups was randomized. The clinical parameters, plaque index (PI), gingival index (GI), probing pocket depth (PPD), clinical attachment level (CAL), and bone fill, were recorded at different time intervals at the baseline, 1 month, 3 months, and 6 months. Intraoral radiographs were taken using standardized paralleling cone technique at baseline, 1, 3, and 6 months. Statistical analysis was done by using the one-way analysis of variance (ANOVA) followed by Tukey highly significant difference. Results: Both groups resulted in decrease in probing depth (group A, 3.0 mm; group B, 2.83 mm) and gain in clinical attachment level (group A, 3.33 mm; group B, 3.0 mm) over a period of 6 months, which was statistically insignificant. Conclusion: Within the limitations of the present study, it can be concluded that both mineralized cancellous bone allograft (Puros®) or autogenous bone result in significant clinical improvements. PMID:28217545

  3. Posterior lumbar inter-body fusion (PLIF) using autogenous bone and cage with pedicle screw instrumentation versus PLIF using cage with pedicle screw instrumentation in adult spondylolisthesis

    Institute of Scientific and Technical Information of China (English)

    Dou Yusheng; Hao Dingjun; Wen Shiming

    2005-01-01

    Objective: To compare the clinical outcomes of PLIF using autogenous bone and cage with pedicle screw fixation (group 2) and simple cage fusion with pedicle screw fixation (group 1) in adult spondylolisthesis.Methods: 27 patients with minimum follow-up of 24 months, treated by inter-body fusion with pedicle screw fixation were prospectively studied. Disc space height, degree of slippage and fusion rate had been compared before and after operation between the two groups. Results: After minimum 24 month's follow-up, there was no significant difference between the two groups in terms of the amount of blood loss, duration of hospital stay, back pain,radiating pain, fusion rate, or complication (P>0.05). however, there was a significant difference between the two groups in terms of disc space height and percentage of slippage (P<0.05). Conclusion: PLIF using autogenous bone and cage with pedicle screw fixation more beneifical to improve fusion rate and prevent long-term instabilities than simple cage fusion with pedicle screw fixation in adult spondylolisthesis.

  4. Reconstruction of mandibular vertical defects for dental implants with autogenous bone block grafts using a tunnel approach: clinical study of 50 cases.

    Science.gov (United States)

    Restoy-Lozano, A; Dominguez-Mompell, J L; Infante-Cossio, P; Lara-Chao, J; Espin-Galvez, F; Lopez-Pizarro, V

    2015-11-01

    The objective of this study was to evaluate the outcomes of mandibular vertical defect reconstruction with autologous bone and the use of a sub-periosteal tunnel approach in preparation for dental implant insertion. Forty-three consecutive patients with an atrophic posterior mandible were reconstructed using this method. Two thin laminae of cortical bone, obtained by splitting blocks harvested from the retromolar area, were fixed in a box-like framework containing cancellous and particulate bone. The goal was to achieve an alveolar ridge width of ≥5.5mm and an effective bone height (EBH) of ≥10.5mm for dental implant insertion (≥3.4mm diameter, ≥9.5mm length). Fifty reconstruction procedures were performed. The mean EBH was 7.1±1.3mm pre-treatment and 12.3±1.1mm post-treatment (mean increase 5.2±1.4mm). Complete graft loss was recorded in two cases; the remaining complications were minor. After a mean consolidation period of 3.5 months, 96 dental implants were placed. No failure of osseointegration was observed at follow-up (mean 32.9 months). The average bone height reduction was 0.9mm (graft vertical resorption 17.4%). Reconstruction of posterior mandibular vertical defects using two autogenous cortical bone blocks with particulate bone between them, combined with a tunnelling technique, provided good healing with no wound dehiscence and minimum resorption of the grafted bone, favouring a substantial vertical bone gain.

  5. Filling of extraction sockets with autogenous bone in cats Preenchimento de alvéolos dentais de gatos com osso autógeno

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    Adelina Maria da Silva

    2012-01-01

    Full Text Available PURPOSE: To evaluate bone healing in the extraction socket of the feline mandibular canine tooth after grafting. METHODS: Eighteen adult cats were submitted to unilateral extraction of mandibular canine tooth and divided into three groups. In group 1 (n=6, control, the extraction socket was left empty. In group 2 (n=6, the extraction socket was filled with autogenous cancelous bone from the iliac crest and in group 3 (n=6, with cortical bone chips from the iliac crest. Cats were euthanized at 6 weeks postoperative. RESULTS: Immediate postoperative radiographs in dorsoventral view showed a radiolucent area at the extraction wound. A decreased radiolucency was observed on the radiographs taken at 6 weeks postoperative. Histological examination showed formation of woven bone within the extraction socket. The percentage of newly formed bone within the extraction socket, measured by the histometry, showed no statistically significant difference among the values of the three groups (Kruskal-Wallis'test p>0.05 (group 1: 52.54 ± 15.46, group 2: 50.51 ± 5.01, group 3: 51.85 ± 9.52. CONCLUSION: The bone regeneration observed in the extraction sockets filled with autogenous cancellous bone or autogenous cortical bone chips was similar to that observed in the control sites, given an observation period of 6 weeks after extraction of the mandibular canine tooth.OBJETIVO: Avaliar a regeneração óssea de alvéolos dentais de gatos após enxertia. MÉTODOS: Dezoito gatos adultos, distribuídos em três grupos de 6 animais cada, foram submetidos a extração do canino mandibular direito ou esquerdo. No grupo 1, controle, o alvéolo foi deixado vazio. No grupo 2, o alvéolo foi preenchido com osso esponjoso autógeno do osso ilíaco e no grupo 3, com raspa de osso cortical do osso ilíaco. Os animais foram submetidos à eutanásia 6 semanas após a cirurgia. RESULTADOS: Nas radiografias realizadas no pós-operatório imediato na projeção ventrodorsal

  6. "Plug" ósseo autógeno para orifícios de trepanação: nota técnica Autogenic bone plug to seal burr holes: technical note

    Directory of Open Access Journals (Sweden)

    JOSUÉ GUIMARÃES GRANHA VIALOGO

    1999-12-01

    Full Text Available Vários materiais são utilizados para ocluir os orifícios de trepanação em neurocirurgia, por motivos variados: para evitar fístula liquórica após trepanações, para auxiliar a fixação do "flap" ósseo e por motivos estéticos, na região frontal. Dentre estes materiais citamos os heterólogos (botões de silicone, miniplacas de metal, cera de osso, metilmetacrilato, gelfoam, cimento de polímero vegetal, cerâmica de hidroxiapatita, e os autólogos (pó de osso originado da trepanação, gordura, músculo, aponeurose. Os materiais heterólogos ou sintéticos podem provocar reação de corpo estranho com erosão da pele e exposição do material, tornando necessária sua retirada, em tempo variável no pós-operatório. Há cerca de três anos, o autor vem utilizando um botão ou "plug" ósseo autólogo, feito com surgicel e o pó de osso proveniente da trepanação, com bom resultado estético eliminando as desconfortáveis depressões cranianas pós-trepanação. Apresentamos a técnica de confecção deste prático `plug ósseo autólogo'. Nas neuroendoscopias, praticamente sanou-se o problema da fístula liquórica e reação de corpo estranho. Encorajamos a utilização deste botão ósseo autólogo em nosso meio, como método eficiente, econômico e biologicamente aceitável para ocluir orifícios cranianos de trepanação.Many neurosurgical procedures can be performed by a single burr hole: neuroendoscopy, microvascular decompression, stereotactic procedures, chronic subdural haematomas. It is technically difficult to suture and close the dura, located at the bottom of such holes, which can lately lead to CSF leakage. On the other hand, the surgical material used to seal the burr holes can be divided in heterogenic (metal screws, silicon plugs, gelfoam, bone wax, metilmetacrilate, hidroxiapatite, and autogenic (fat, aponeurosis, muscle, and bone dust from trephination. The heterogenic group always brings the possibility of

  7. 自体牙本质片修复骨缺损的实验研究%Pilot study of autogenous tooth dentin graft to repair bone defect

    Institute of Scientific and Technical Information of China (English)

    秦旭; 石玮; 马博; 许译文; 陈卫民; 周彬

    2014-01-01

    Objective:To investigate the feasibility of autogenous dentin block to repair the bone defect. Method:Autogenous grafts from freshly extracted teeth were rigidly fixed to the mandibular defects in eighteen rabbits using titanium screws in order to achieve good primary stability. Every six rabbits were stochastically sacrificed at 1,3 and 6 months after implantation respectively. For all specimens,radiographical and histological measurements were performed. Result:The boundaries of the grafts were distinctly visible in the implanted area during the first and third month. However,the teeth grafts were fully covered by new bone after sixth month. The radiograph demonstrated the progressive change in the bone and grafted tooth interface from radiolucency to radiopacity. Histologically,vascularization led to a temporary fibrous-integration in the graft-bone interface and grafts were gradually resorbed and replaced by new bone. Conclusion:Rigid fixation of auto-genous tooth dentin could serve as a novel approach for bone regeneration and to repair of bone defect.%目的:探讨自体牙本质片修复骨缺损的临床效果。方法:选取18只2.5~3 kg新西兰兔,随机分为3组,拔取自体下切牙,制备成牙本质片,在同侧下颌骨下缘制备骨缺损,用钛钉坚固内固定牙本质片于缺损区。分别在术后1、3、6个月取材进行影像学和组织学检查。结果:术后1、3个月仍可见牙本质片与骨组织存在分界,但6个月时牙本质片完全被骨组织覆盖。放射学检查提示牙本质片与骨组织间的低密度投射影随着植入时间延长而逐渐消失,高密度影逐渐形成。组织学显示牙本质片与骨组织界面血管化,牙本质片逐渐被吸收,新骨形成。结论:坚固内固定的自体牙本质片能作为骨缺损修复材料恢复骨缺损。

  8. Comparative study between cortical bone graft versus bone dust for reconstruction of cranial burr holes

    OpenAIRE

    Worm, Paulo Valdeci; Ferreira,Nelson Pires; Faria, Mário de Barros; Ferreira, Marcelo Paglioli; Kraemer,Jorge Luiz; Collares, Marcus Vinicius Martins

    2010-01-01

    Background: As a consequence of the progressive evolution of neurosurgical techniques, there has been increasing concern with the esthetic aspects of burr holes. Therefore, the objective of this study was to compare the use of cortical bone graft and bone dust for correcting cranial deformities caused by neurosurgical trephines. Methods: Twenty-three patients were enrolled for cranial burr hole reconstruction with a 1-year follow-up. A total of 108 burr holes were treated; 36 burr holes were ...

  9. Variables Affecting Fusion Rates in the Rat Posterolateral Spinal Fusion Model with Autogenic/Allogenic Bone Grafts: A Meta-analysis.

    Science.gov (United States)

    Ishida, Wataru; Elder, Benjamin D; Holmes, Christina; Lo, Sheng-Fu L; Witham, Timothy F

    2016-11-01

    The rat posterolateral spinal fusion model with autogenic/allogenic bone graft (rat PFABG) has been increasingly utilized as an experimental model to assess the efficacy of novel fusion treatments. The objective of this study was to investigate the reliability of the rat PFABG model and examine the effects of different variables on spinal fusion. A web-based literature search from January, 1970 to September, 2015, yielded 26 studies, which included 40 rat PFABG control groups and 449 rats. Data regarding age, weight, sex, and strain of rats, graft volume, graft type, decorticated levels, surgical approach, institution, the number of control rats, fusion rate, methods of fusion assessment, and timing of fusion assessment were collected and analyzed. The primary outcome variable of interest was fusion rate, as evaluated by manual palpation. Fusion rates varied widely, from 0 to 96%. The calculated overall fusion rate was 46.1% with an I (2) value of 62.4, which indicated moderate heterogeneity. Weight >300 g, age >14 weeks, male rat, Sprague-Dawley strain, and autogenic coccyx grafts increased fusion rates with statistical significance. Additionally, an assessment time-point ≥8 weeks had a trend towards statistical significance (p = 0.070). Multi-regression analysis demonstrated that timing of assessment and age as continuous variables, as well as sex as a categorical variable, can predict the fusion rate with R (2) = 0.82. In an inter-institution reliability analysis, the pooled overall fusion rate was 50.0% [44.8, 55.3%], with statistically significant differences among fusion outcomes at different institutions (p fusion outcomes, the reliability of the rat PFABG model was relatively limited. However, selection of adequate variables can optimize its use as a control group in studies evaluating the efficacy of novel fusion therapies.

  10. Maxillary Sinus Floor Augmentation Surgery with Autogenous Bone Grafts as Ceiling: A Pilot Study and Test of Principle

    OpenAIRE

    Raghoebar, Gerry M.; Meijer, Henny J A; Telleman, Gerdien; Vissink, Arjan

    2013-01-01

    Background: Studies have pointed out that the mere elevation of the maxillary sinus membrane might suffice to allow for bone formation indicating the additional use of augmentation materials to be redundant. Purpose: The purpose of this study was to assess whether elevation of the sinus mucosal lining combined with applying an autologous bone graft as a ceiling and placement of a short implant would allow for bone formation around the implant thus surpassing the need for applying augmentation...

  11. Successful use of autogenous bone graft for the treatment of a radius-ulna nonunion in an amputee dog

    Directory of Open Access Journals (Sweden)

    B.W. Minto

    2015-08-01

    Full Text Available Fracture nonunions represent important complications in orthopedic surgeries. Nonunion repairs or bone defects are surgically challenging. Our aim was to describe a nonunion case, which was repaired with rapid bone recovery. An 8-month-old male mixed breed dog that has been previously operated was presented to the Veterinary Medical Teaching Hospital of São Paulo State University, with a right radius-ulna nonunion and an amputated contralateral forelimb. A cancellous bone graft was collected from a partially amputated limb, in order to correct the nonunion, and used in association with a locking plate. After four weeks, the bone graft had been incorporated into the original bone. Clinical union with good weight bearing was achieved after eight weeks.

  12. Maxillary Sinus Floor Augmentation Surgery with Autogenous Bone Grafts as Ceiling : A Pilot Study and Test of Principle

    NARCIS (Netherlands)

    Raghoebar, Gerry M.; Meijer, Henny J. A.; Telleman, Gerdien; Vissink, Arjan

    2013-01-01

    Background: Studies have pointed out that the mere elevation of the maxillary sinus membrane might suffice to allow for bone formation indicating the additional use of augmentation materials to be redundant. Purpose: The purpose of this study was to assess whether elevation of the sinus mucosal lini

  13. Space maintenance in autogenous fresh demineralized tooth blocks with platelet-rich plasma for maxillary sinus bone formation: a prospective study.

    Science.gov (United States)

    Kim, Eun-Suk; Kang, Ji-Yeon; Kim, Jae-Jin; Kim, Kyoung-Won; Lee, Eun-Young

    2016-01-01

    This prospective study evaluated the effectiveness of autogenous fresh demineralized tooth block (Auto-FDT block) with platelet-rich plasma (PRP) for maxillary sinus augmentation with simultaneous implant installation. Auto-FDT block with PRP was used in Group 1 (n = 15) and combined graft (allograft and xenograft) powder with PRP was used in Group 2 (n = 15). For up to 2 years after the final prosthesis was installed, clinical and radiographic examinations were performed to evaluate the amount of graft materials, residual alveolar height (RAH), sinus height (SH) after grafting, augmented graft height (AGH) and resorption height (RH). In ten cases, biopsies were harvested for histological and histomorphometric analyses. A total of 59 implants were placed in a severe atrophic posterior maxilla with less than 5 mm of RAH and sinus augmentation. None of the patients developed sinusitis or other complications, such as implant loss. The graft material extracted included one molar (or 2 premolars) in Group 1 and 1.8 cc in Group 2. The radiologic examination revealed the following average between-group difference SH (Group 1, 14.12 ± 1.63 mm vs Group 2, 16.51 ± 1.29 mm) and AGH (Group 1, 11.62 ± 2.22 mm vs Group 2, 13.65 ± 1.35 mm). However, sufficient SH and AGH were observed for the implants in the Auto-FDT block group. Two years after final prosthesis was installed, no between-group difference in the RH was observed (Group 1, 1.23 ± 0.73 mm vs Group 2, 1.77 ± 0.54 mm, P = 0.021). The histomorphometric analysis revealed no between-group difference in the new bone volume (Group 1, 23.13 ± 1.42 % vs Group 2, 24.18 ± 2.19 %, P = 0.548). The results showed that Auto-FDT block with PRP can be used in grafted sinuses for implants with only one extracted molar (or two premolars). Auto-FDT block with PRP promotes new bone formation that is comparable with combined grafts. Auto-FDT block with PRP is as an alternative to bone grafting

  14. Neglected anterior dislocation of shoulder with large Hillsach's lesion & deficient glenoid: Treated by autogenous bone graft & modified Latarjet procedure☆

    Science.gov (United States)

    Peshin, Chetan; Jangira, Vivek; Gupta, Ravi Kumar; Jindal, Rohit

    2015-01-01

    Neglected anterior dislocation of shoulder is rare in spite of the fact that the anterior dislocation of the shoulder is seen in around 90% of the acute cases. Most of the series of neglected dislocation describe posterior dislocation to be far more common.1,2 We hereby report a case of the neglected anterior shoulder dislocation in a 15 year old boy who had a history of epilepsy. There was a large Hill Sachs lesion in humeral head which was impacted in glenoid inferiorly and glenoid was eburnated at that margin. The humeral head was reconstructed with a tricortical iliac graft. Glenoid was reconstructed by transfer of coracoids process of scapula to antero-inferior glenoid (modified Latarjet procedure). This case is unique because management of humeral head defect with bone graft is not mentioned in anterior dislocation. PMID:26566343

  15. Neglected anterior dislocation of shoulder with large Hillsach's lesion & deficient glenoid: Treated by autogenous bone graft & modified Latarjet procedure.

    Science.gov (United States)

    Peshin, Chetan; Jangira, Vivek; Gupta, Ravi Kumar; Jindal, Rohit

    2015-12-01

    Neglected anterior dislocation of shoulder is rare in spite of the fact that the anterior dislocation of the shoulder is seen in around 90% of the acute cases. Most of the series of neglected dislocation describe posterior dislocation to be far more common.(1) (,2) We hereby report a case of the neglected anterior shoulder dislocation in a 15 year old boy who had a history of epilepsy. There was a large Hill Sachs lesion in humeral head which was impacted in glenoid inferiorly and glenoid was eburnated at that margin. The humeral head was reconstructed with a tricortical iliac graft. Glenoid was reconstructed by transfer of coracoids process of scapula to antero-inferior glenoid (modified Latarjet procedure). This case is unique because management of humeral head defect with bone graft is not mentioned in anterior dislocation.

  16. Mandibular reconstruction: a histological and histomorphometric study on the use of autogenous scaffolds, particulate cortico-cancellous bone grafts and platelet rich plasma in goats.

    NARCIS (Netherlands)

    Fennis, J.P.M.; Stoelinga, P.J.W.; Jansen, J.A.

    2004-01-01

    Twenty-eight goats underwent a continuity resection of the mandibular angle. In all goats primary reconstruction was carried out using specially designed pre-shaped osteosynthesis plates and monocortical screws. The original cortical scaffold was used to bridge the defect, filled with an autogenous

  17. 人工骨加自体骨修复中老年外伤性前牙牙槽骨缺损的临床研究%Clinical study of the artificial bone and autogenous bone in repairing traumatic anterior alveolar bone defects in the middle-aged and elderly people

    Institute of Scientific and Technical Information of China (English)

    廖福琴; 朱菲; 张昊; 张丽军

    2013-01-01

    目的 探讨胶原基纳米骨(nHAC)加自体骨修复中老年外伤性前牙牙槽骨缺损的临床疗效.方法 选择23例中老年因外伤前牙牙槽骨缺损需植骨者,用nHAC加术区游离的自体骨修复缺损,采用固定正畸技术对松动牙进行固定.术后1、2、3、6、12个月复诊,术前术后均对病损部位进行临床及X线检查,观察缺损程度及新骨形成和骨密度改变.结果 nHAC加自体骨修复中老年外伤性前牙牙槽骨缺损愈合成功率95.65%,脱位牙复位固定治疗成功率88.23%,所有患者无不良症状和体征,牙槽骨高度和宽度明显得到改善.X线片显示:胶原基纳米骨(nHAC)加自体骨植入区可见新生骨小梁,骨密度增强,骨质疏松有所改善,植入骨与宿主骨组织融为一体,牙槽骨缺损修复.结论 nHAC加自体骨修复外伤性前牙牙槽骨缺损可以增强牙槽骨密度,恢复牙槽骨的丰满度,保留了更多的牙齿,也为义齿修复提供了良好的生理基础.%Objective To investigate the clinical efficacy of the mixture of nano-hydroxyapative/collagen composite (nHAC)and autogenous bone on repairing traumatic anterior alveolar bone defects in the middle-aged and elderly people.Methods Twenty-three middle-aged and elderly patients,who had traumatic anterior alveolar bone defects and needed bone transplanting,were selected.They were treated with the mixture of nHAC and autogenous bone to repair the traumatic alveolar bone defects.Edgewise appliance was used for reduction and fixation in traumatic dislocated teeth.After1,2,3,6,and 12 months,all the patients needed subsequent visit.Clinical and X-ray examination of bone defects were performed to observe the degree of bone defects,new bone formation,and bone mineral density before and after the treatment.Results Among all the 23 patients,the therapeutic effective rate of using the mixture of nHAC and autogenous bone to repair traumatic anterior alveolar bone defects was 95.65

  18. Applied anatomy of ankle lateral ligament reconstruction with periostum-patellar tendon-bone autogenous graft%自体髌骨膜-髌韧带-骨瓣重建踝外侧韧带的应用解剖

    Institute of Scientific and Technical Information of China (English)

    孙强; 周捍东; 郑加法

    2011-01-01

    目的 为自体髌骨膜-髌韧带-骨瓣重建踝关节外侧韧带提供解剖学基础.方法 在6侧经防腐同定的成人下肢标本及6侧新鲜标本上观测踝关节外侧韧带起止点及走行径路、髌韧带的解剖形态与起止点,在新鲜标本上摹拟重建手术.结果 髌韧带位置恒定,解剖层次表浅,切取方便,髌骨膜-髌韧带一骨瓣的髌韧带长度(4.1±0.4)cm,距腓前韧带长度(2.4±0.5)cm,跟腓韧带长度(3.1±0.4)cm.结论 (1)髌骨膜-髌韧带-骨瓣的髌韧带具有足够的长度,可形成移植供体;(2)髌骨膜-髌韧带-骨瓣复合体两端分别与骨及软骨创面固定,容易成活和恢复功能;(3)采用自体髌骨膜-髌韧带-骨瓣重建踝外侧韧带具有可行性.%Objective To provide anatomic basis for free autogenous periostum- patellar tendon-bone grafts to reconstruct the lateral ankle ligament.Methods The anatomic properties of lateral ankle and patellar ligaments were observed and measured on 12 adult cadavers, and the reconstruction of the lateral ankle ligament were simulated on 6 fresh specimens.Results The constant locations of the patellar ligament were easy to be incised; The lengths of the patellar ligaments and the calacaneofibular and anterior talofibular ligaments were (41.0 ±4.0)mm, (24.3 ±4.6)mm and (31.3 ±4.2)mm, respectively.Conclusions The anatomic properties of periostum-patellar tendon-bone was similar to that of lateral ankle ligaments, There were periostum-patellar tendon-bone ligament tissue with enough length for the lateral ankle joint ligaments reconstruction.The grafted periostum- patellar tendon-bone easily can survive on recipient site.Autogenous periostum- patellar tendon-bone Grafts could to be used to reconstruct the lateral ankle joint ligaments.

  19. Autogenous Deformation of Concrete

    DEFF Research Database (Denmark)

    Autogenous deformation of concrete can be defined as the free deformation of sealed concrete at a constant temperature. A number of observed problems with early age cracking of high-performance concretes can be attributed to this phenomenon. During the last 10 years , this has led to an increased...... focus on autogenous deformation both within concrete practice and concrete research. Since 1996 the interest has been significant enough to hold international, yearly conferences entirely devoted to this subject. The papers in this publication were presented at two consecutive half-day sessions...... at the American Concrete Institute’s Fall Convention in Phoenix, Arizona, October 29, 2002. All papers have been reviewed according to ACI rules. This publication, as well as the sessions, was sponsored by ACI committee 236, Material Science of Concrete. The 12 presentations from 8 different countries indicate...

  20. Veterinary autogenous vaccines.

    Science.gov (United States)

    Hera, A; Bures, J

    2004-01-01

    Autogenous vaccines remain a regulatory issue. They are demanded by practising veterinarians and by animal owners and they are quite widely used, mainly in Central European Countries, the Czech Republic, Hungary and Slovak Republic having probably the longest tradition with these products in Central Europe. The scope given in Article 3, Para. 2 (and/or Article 4 for some countries) of Directive 2001/82/EC applies to these products in the Acceding Countries. As these products are exempt from the harmonised regulation at the EU level, they are regulated by individual countries, the regulation varying from practically no regulatory measures in certain countries to a quite complex and demanding regulation in the other countries. Both risks and benefits are related to these products and they shall be taken into account when regulatory measures are considered. The major risks related to veterinary autogenous vaccines relate to possibility of transmission of TSE agents or other viral, bacterial and/or fungal contaminants. As appropriate and well balanced regulation of these products is deemed necessary, considering the risks related to these products, and based on the fact that national regulatory measures could be considered as a trade barrier under certain circumstances, harmonisation of the key issues or legal admission of the nationally based regulatory measures, including movement of these products from the other Member States, shall be laid down in the EU legislation. The veterinary autogenous vaccines complying with basic quality and safety requirements are thus a very useful tool in the animal health and welfare management but their use should be restricted to situations where there is no authorised veterinary medicinal product available and veterinary autogenous vaccines must not be allowed to replace good farming or veterinary practices.

  1. AUTOGENIC THERAPY IN TENSION HEADACHE

    OpenAIRE

    Amruthraj, Brunda; Mishra, H.; Kumaraiah, V.

    1987-01-01

    SUMMARY Ten subjects diagnosed as Psychalgia were taken for study. A multiple baseline design was adapted and clients were subjected to 30 sessions of autogenic training. They were assessed using physiological (EMG and thermal change) and behavioural measures (Visual analogue scale and behavioural symptom checklist). Findings revealed autogenic therapy to be effective in reducing tension headache.

  2. BMP-2基因修饰自体BMSCs移植促进兔下颌骨牵张成骨新骨形成的实验研究%EXPERIMENTAL STUDY ON TRANSPLANTATION OF BMP-2 GENE TRANSFECTED AUTOGENOUS BONE MESENCHYMAL STEM CELLS FOR PROMOTING BONE REGENERATION IN RABBIT MANDIBULAR DISTRACTION OSTEOGENESIS

    Institute of Scientific and Technical Information of China (English)

    黄旋平; 周诺; 江献芳; 杨媛媛; 李华; 谢庆条

    2012-01-01

    目的:检测骨形态发生蛋白-2(BMP-2)基因mRNA及其蛋白的表达,探讨BMP-2基因修饰自体骨髓间充质干细胞(BMSCs)移植对兔下颌骨牵张成骨新骨形成的促进作用.方法:取新西兰白兔36只随机分为3组,每组12只.建立牵张成骨动物模型,在固定期第2天,实验组于牵张间隙注射200 μL的BMP-2基因修饰的自体BMSCs液;对照组注射等量自体BMSCs液;空白组注射等量生理盐水.分别于固定2,6周通过逆转录多聚酶链式反应(RT-PCR)、免疫组化等手段检测BMP-2基因mRNA及其蛋白的表达情况.结果:实验组牵张间隙新生骨组织均可见BMP-2基因mRNA和其蛋白强阳性表达.结论:BMP-2基因修饰的自体BMSCs移植能有效促进兔下颌骨牵张成骨新骨形成.%Objective:To examine the expressions of both bone morphogenetic protein-2 (BMP-2) gene mR-NA and related proteins and investigate the promotive effect of transplantation of BMP-2 gene transfected autogenous bone mesenchymal stem cells on bone regeneration in rabbit mandibular distraction osteogene-sis. Methods: Thirty-six New Zealand's white rabbits were randomly divided into three groups with twelve in each. All objects -were prepared into distraction osteogenesis surgical model on right mandibles. On the 2nd day of consolidation, experimental, control, and blank groups -were injected -with the same amount of 200 juL of the solution with BMP-2 gene transfected autogenous bone mesenchymal stem cells, the solution with autogenous bone mesenchymal stem cells, and physiological saline at distraction gap, respectively. The expressions of BMP-2 mRNA and related proteins -were examined by RT-PCR and immunohistochem-istry at the ends of the 2nd and 6th -week consolidations, respectively. Results: Strongly positive expression of both BMP-2 gene mRNA and related proteins were confirmed on regenerated bone in distraction gap. Conclusion: The transplantation of BMP-2 gene transfected autogenous bone

  3. A 10-year follow-up of transpedicular screw fixation and intervertebral autogenous posterior iliac crest bone graft or intervertebral B-Twin system in failed back surgery syndrome

    Science.gov (United States)

    Cincu, Rafael; Lorente, Francisco de Asis; Gomez, Joaquin; Eiras, Jose; Agrawal, Amit

    2015-01-01

    Background: The spine surgeons have been combining anterior and posterolateral fusion (circumferential fusion) as the final solution to treat spinal disorders and many have been using it to treat failed back surgery syndrome (FBSS). In present study, we analyzed and compared the clinical and radiological outcomes in patients with transpedicular screw fixation and intervertebral autogenous posterior iliac crest bone graft or in patients with transpedicular screw fixation and intervertebral B-Twin system for FBSS with a follow-up period of 10 years after the surgery. Materials and Methods: This study was a retrospective case study performed on 55 patients with FBSS. Clinical and radiological changes were compared between the two groups of patients on the basis of improvement of back pain, radicular pain, and work capacity. Outcome was measured in terms of Oswestry Low Back Pain Disability Index, and the changes in pain and function were documented every year from before surgery until 2012. We analyzed the evolution of 55 cases of FBSS those underwent segmental circumferential posterior fusions from June 2001 to February 2003, operated by a single surgeon and followed up during 10 years until February 2012. The patients were divided into 2 groups: In 25 patients, posterolateral fusions with Legacy™ (Medtronic, Inc. NYSE: MDT) screws and intersomatic autogenous posterior iliac crest bone graft was performed, and, in 30 patients, posterolateral fusions with the same screws and intersomatic fusion B-Twin (Biomet Spain Orthopaedics, S.L.) system was performed. In all cases, we used posterior lumbar interbody fusion (PLIF)/transforaminal lumbar interbody fusion (TLIF) approach for intervertebral graft, and the artrodesis was supplemented at intertransverse level with Autologus Growth Factor (AGF-MBA INCORPORADO, S.A.). The outcome was measured in terms of Oswestry Low Back Pain Disability Index, and the changes in pain and function were documented every year and compared

  4. Horizontal Bone Augmentation Using Autogenous Block Grafts and Particulate Xenograft in the Severe Atrophic Maxillary Anterior Ridges: A Cone-Beam Computerized Tomography Case Series.

    Science.gov (United States)

    Monje, Alberto; Monje, Florencio; Hernández-Alfaro, Federico; Gonzalez-García, Raúl; Suárez-López del Amo, Fernando; Galindo-Moreno, Pablo; Montanero-Fernández, Jesús; Wang, Hom-Lay

    2015-07-01

    The aim of the present study was to use cone-beam computerized tomography (CBCT) to assess horizontal bone augmentation using block grafts, harvested from either the iliac crest (IC) or mandibular ramus (MR) combined with particulate xenograft and a collagen membrane for in the severe maxillary anterior ridge defects (cases Class III-IV according to Cadwood and Howell's classification). Fourteen healthy partially edentulous patients requiring extensive horizontal bone reconstruction in the anterior maxilla were selected for the study. Nineteen onlay block grafts (from IC or MR) were placed. The amount of horizontal bone gain was recorded by CBCT at 3 levels (5, 7, and 11 mm from the residual ridge) and at the time of bone grafting as well as the time of implant placement (≈5 months). Both block donor sites provided enough ridge width for proper implant placement. Nonetheless, IC had significantly greater ridge width gain than MR (Student t test) (4.93 mm vs 3.23 mm). This was further confirmed by nonparametric Mann-Whitney test (P = .007). Moreover, mean pristine ridge and grafted ridge values showed a direct association (Spearman coefficient of correlation = .336). A combination of block graft, obtained from the IC or MR, combined with particulate xenograft then covered with an absorbable collagen membrane is a predictable technique for augmenting anterior maxillary horizontal ridge deficiency.

  5. Mechanical properties of radial bone defects treated with autogenous graft covered with hydroxyapatite in rabbit Propriedades mecânicas de defeito de osso radial tratado com enxerto autógeno coberto com nano-hydroxyapatite em coelho

    Directory of Open Access Journals (Sweden)

    Davood Sharifi

    2012-03-01

    Full Text Available PURPOSE: To determine biomechanical property of autogenous bone graft covered with hydroxyapatite in the defect of radial bone in rabbit. METHODS: Eighteen adult male New Zealand white rabbits were used which were divided into three groups (I, II, III of six rabbits each. A segmental bone defect of 10 mm in length was created in the middle of the right radial shaft under general effective anesthesia in all rabbits and were stabilized using mini-plate with four screws. The defects In group I were left as such without filler, whereas in group II the defect were filled up with harvested 10 mm rib bone and in group III the defect were packed with rib bone covered with nano-hydroxyapatite. All rabbits in three groups were divided into two subgroups (one month and three months duration with three rabbits in each one. RESULTS: The mechanical property and the mean load for fracturing normal radial bone was recorded 388.2±6 N whereas it was 72.4±12.8 N for group I in 1 month duration which was recorded 182.4±14.2 N for group II and 211.6±10.4 N for group III at the end of 1 month. These values were 97.6±10.2 N for group I and 324.6±8.2 N for group II and 372.6±17.4 N for group III at the end of three months after implantation. CONCLUSION: Implantation of autologous graft covered with hydroxyapatite indicated to have positive effect in integral formation of qualitative callus at the site of fracture and early re-organization of callus to regain mechanical strength too.OBJETIVO: Determinar as propriedades biomecânicas de enxerto ósseo autógeno coberto com hidroxiapatita em defeito do osso radial em coelhos. MÉTODOS: Foram utilizados 18 coelhos adultos, machos, brancos, Nova Zelândia, distribuídos em três grupos (I, II, III de seis coelhos cada. Um defeito segmentar de 10 mm de comprimento foi criado no meio do eixo radial direito sob anestesia geral efetiva em todos os coelhos e foram fixados usando mini-placa com quatro parafusos. Os

  6. Comparison of rhBMP-2 versus Autogenous Iliac Crest Bone Graft for 2-Level Anterior Cervical Discectomy and Fusion for Cervical Spondylotic Myelopathy

    OpenAIRE

    2015-01-01

    Background Few studies have examined the efficacy of recombinant human bone morphogenetic protein-2 (rhBMP-2) in 2-level anterior cervical discectomy and fusion (ACDF). The purpose of this study was to compare the outcomes in a series of patients with CSM treated with 2-level ACDF with or without rhBMP-2. Material/Methods The retrospective study included a total of 146 patients with CSM. The rhBMP-2 group consisted of 73 patients who underwent 2-level ACDF with rhBMP-2. A total of 73 patients...

  7. Autogenous tooth transplantation: an alternative to replace extracted tooth

    Directory of Open Access Journals (Sweden)

    David B. Kamadjaja

    2015-09-01

    Full Text Available Background: The gold standard treatment to replace missing tooth is dental implants, however, in certain cases, such as in young patients its placement is contraindicated. Autogenous tooth transplantation, which has been widely done in Scandinavian countries for many years, may become a good alternative to overcome this problem. Purpose: This article attempted to provide information about the indication, treatment planning, surgical technique and the successful result of autogenous tooth transplantation. Case: A fifteen year old male patient presented with large caries and periapical disease of his lower left first molar, which was partially erupted and the roots was not fully formed in radiograph. Case management: Autogenous tooth transplantation procedure was performed consisting of extraction of #36, odontectomy of #38 followed by its implantation to socket #36 and fixation of the transplanted tooth to the adjacent teeth. Post operative evaluation was done on regular basis within 18 months period. There was no complaint, the tooth was clinically stable and no evidence of periodontal problem. Serial radiographs showed healing of alveolar bone and periodontal tissue, and the complete root formation was evident by 18 months post operatively. Conclusion: Autogenous tooth transplantation is a potential alternative to replace extracted tooth. Provided that the case be properly planned and operation carefully performed, successful result of this treatment can be achieved.

  8. Autogenous Transplantation for Replacing a Hopeless Tooth

    Science.gov (United States)

    Zakershahrak, Mehrsa; Moshari, Amirabbas; Vatanpour, Mehdi; Khalilak, Zohreh; Jalali Ara, Afsoon

    2017-01-01

    Autogenous tooth transplantation (ATT) is a simple and reasonable choice for replacing the missing teeth when a proper donor tooth is available. This report presents a case of successful ATT of a maxillary right third molar for replacement of mandibular right second molar with a concomitant endodontic-periodontal disease. The mandibular second molar was believed to be hopeless due to a severe damage to coronal tooth structure, inappropriate root canal treatment and apical radiolucency. After extraction of mandibular second molar and maxillary third molar (the donor), the tooth was re-implanted into the extracted socket of second molar site. Root canal therapy was then performed. After 3 years, clinical and radiographic examinations revealed satisfying results, with no signs and symptoms. The patient is asymptomatic and the transplanted tooth is still functional with no signs of marginal periodontal pathosis. Radiographies showed bone regeneration in the site of previous extensive periapical lesion, normal periodontal ligament with no signs of root resorption. PMID:28179939

  9. 钛网结合异体骨移植联合人骨形成蛋白与自体骨移植在种植前牙槽嵴骨增量中的应用对比%Comparison of Application of Titanium Mesh Combined with Allograft Combined with Human Bone Morphogenetic Protein and Autogenous Bone Transplantation in Alveolar Bone Augmentation

    Institute of Scientific and Technical Information of China (English)

    崔延军; 王红光; 程汇

    2015-01-01

    Objective To compare the application of titanium mesh combined with allograft combined with human bone morphogenetic protein and autogenous bone transplantation in alveolar bone augmentation.Methods A total of 46 cases receiving anterior implant plus alveolar bone increment admitted to Tianmen City First People′s Hospital from Jan.2008 to Dec.2011 were randomly divided into two groups according to random-number table method,group A(n =23) using titanium mesh combined with allograft combined with human bone morphogenetic protein,while group B (n =23) using autogenous bone graft.The alveolar ridge width,the incremental effects and postoperative bone implant stability were compared before and after surgery.Results Postoperative average alveolar ridge width of group A was significantly higher than that of group B [(6.9 ±0.5) mm vs (5.6 ±0.3) mm,P <0.01]; the cure rate of group A was 94.1%,of group B was 60.0%,and the clinical efficacy of group A was better than group B with statistically significant difference (P <0.05); no-loosening rate after 4 months implant was 91.2% in group A,50.6% in group B,the sta-bility of group A was much better than group B,with statistically significant difference(P <0.05).Conclu-sion Titanium mesh combined with allogeneic bone graft combined with human bone morphogenetic protein can significantly increase patient alveolar bone mass and help to stabilize the implant after surgery .%目的:比较钛网结合异体骨移植联合人骨形成蛋白与自体骨移植在种植前牙槽嵴骨增量中的应用效果。方法将2008年1月至2011年12月天门市第一人民医院收治的46例前牙种植并行牙槽嵴骨增量的患者依据随机数字表法分为两组:A 组23例,采用钛网结合异体骨移植联合人骨形成蛋白的方法;B 组23例,采用自体骨移植的方法。比较两组患者手术前后牙槽嵴宽度、骨增量效果及术后种植体稳定性。结果术后 A 组牙槽嵴

  10. Computed tomography evaluation of autogenous graft in sinus lift surgery; Analise por tomografia computadorizada do enxerto autogeno na cirurgia de 'sinus lift'

    Energy Technology Data Exchange (ETDEWEB)

    Ajzen, Sergio Aron; Moscatiello, Rafael Andrade; Lima, Aida Maria Custodio de; Moscatiello, Vitoria Aparecida Muglia; Helio Kiitiro Yamashita [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. de Diagnostico por Imagem; Mosacatiello, Rafael Muglia; Nishiguchi, Celso Itiro [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Disciplina de Tecnica Operatoria e Cirurgia Experimental; Alves, Maria Teresa de Seixas [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Disciplina de Anatomia Patologica

    2001-02-01

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

  11. Viability of autogenous bone grafts obtained by using bone collectors: histological and microbiological study Viabilidade dos enxertos autógenos obtidos com a utilização de coletores para osso: estudo histológico e microbiológico

    Directory of Open Access Journals (Sweden)

    Alberto Blay

    2003-09-01

    Full Text Available The use of autogenous bone grafts is considered to be the best choice for reconstructive surgery. In the periodontal literature, the utilization of osseous coagulum was suggested by the end of the sixties. The purpose of this study is to consider the use of bone collectors (bone traps as an alternative method for obtaining material to fill small bone imperfections, such as fenestrations and dehiscences. Thirty samples were obtained from bone drilling during fixture installation in patients (13 men and 17 women, with an average age of 54 years requiring treatment at the Department of Periodontology and Implant Dentistry, University of Santo Amaro. These samples were fixed in 10% neutral formaldehyde for 24 hours and subjected to histological preparation, in order to evaluate the presence of viable osteoblasts. In addition, the material was placed in a fluid thioglycolate medium and incubated for 24 hours at 36 ± 1°C in aerobiosis and anaerobiosis. Bacterial growth evaluation was made by using six different culture media (MacConkey agar, blood agar base, mannitol salt agar, Anaerokit LTD medium, Anaerokit LTD - bile medium, Anaerinsol. The results show that, if proper care is taken to prevent saliva contamination during the surgical procedure, this method of collecting autogenous bone may be useful in situations where small amounts of bone are required.A utilização de enxertos autógenos é considerada a melhor opção nos tratamentos cirúrgicos de reconstrução óssea. Na literatura periodontal, a utilização de coágulo ósseo foi sugerida no final da década de 60. O objetivo deste estudo é considerar a utilização de coletores para osso como um método alternativo de se obter osso autógeno para preenchimento de defeitos ósseos como fenestrações e deiscências. Trinta amostras foram obtidas no processo de perfuração do tecido ósseo, durante a instalação de implantes em pacientes (13 homens e 17 mulheres, com média etária de

  12. Polímero derivado de mamona acrescido de cálcio, associado ou não à medula óssea autógena na reparação de falhas ósseas Castor oil plant polymer and calcium associated or not to autogenous bone marrow in bone gaps repair

    Directory of Open Access Journals (Sweden)

    Ricardo Junqueira Del Carlo

    2003-12-01

    ítio heterotópico, o implante foi incapaz de osteoindução e histologicamente, em ambos os sítios de implantação foram identificadas células gigantes e tecido fibroso envolvente.In order to evaluate tissue repair after the use of castor oil polymer implant additioned with 40% sodium carbonate, isolated or associated to autogenous bone marrow in heterotopic site and in experimental bone gaps in radii of rabbits, 30 White New Zealand rabbits were submitted to bilateral radial ostectomy. In 15 rabbits the bone gap of the right side was filled with polymer cylinders (group P of similar size of the gaps; the remaining rabbits received autogenous bone marrow with the implant (group M. The bone defects of the left limb did not receive any treatment and served as control. Six rabbits received 6 implants in the Rectus abdominus muscle (heterotopic site and in three of these rabbits the implants was associated with bone marrow. In the radiographic study both groups presented increased radiopacity at the implant site without bone axis deviation or resorption of the receptor bone ends. Group P presented irregular calcification areas at the peripheral region and over the polymer. Group M presented a more intense, regular and precocious radiopacity pattern in relation to group P. In microscopical evaluation there was evidence of immature bone tissue formation tending to organize itself, isolated sprouts of neoformed bone over the polymer and its superficial pores. It was concluded that implant allows osteogenenesis and osteoconduction in bone gaps, and bone formation was progressive, especially when additioned bone marrow aspirate; there was capillary, perivascular tissue and osteoprogenitor cells migrating into the pores; with fibrovascular tissue permeating implant surface; implants incorporation was slowly and was found incomplete until 9 weeks; the implant was able to induce foreign body reaction without toxic or secondary reactions to its presence. In heterotopic and orthotopic

  13. Decalcificated human dentin matrix in autogenous repair of skull defects

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@In the management of traumatic skull defect, the classical treatment has usually been adopted, i.e.,primary debridement and secondary repair of bone defect, especially in cases of open lacerated skull fracture. 1 In general, the use of prosthetic material in repair is often not so satisfactory either in China or abroad. Decalcificated human dentin matrix (DHDM)has been used in autogenous repair of traumatic skull defect in primary operation and a good curative effect has been gained since the time from September 1996 to March 1998. Clinical results and CT scanning observation are reported in the following.

  14. 自体颏部块状骨移植二期种植修复上颌前牙区骨量不足的临床研究%Clinical research of autogenous chin bone graft and secondary implantation in repairing the bone deficiency of anterior maxilla

    Institute of Scientific and Technical Information of China (English)

    田柳; 周巧珍; 郑瑞斌; 麻健丰

    2014-01-01

    Objective: To demonstrate the clinical effectiveness of ridge augmentation by using autogenous chin graft for the lack of bone mass of the anterior maxilla, following by secondary ITI implantation. Methods: From July 2009 to May 2012, 21 patients with severe alveolar ridge resorption in anterior maxilla were included in this survey. The patients` age ranged from 18 to 42 with an average age of 27.7 years old. 14 out of the 21 patients presented with missing single tooth while the rest of 7 lost multiple teeth. A total of 28 implants were embedded. Bone grafts harvested from mandible chin were used for augmentation. Results:After 4.5 to 10.0 months healing period (mean 6.3 months), 21 patients underwent dental implants placement, 3 to 9 months later(mean 5.2 months)these implants were all re-stored with ceramic crowns/bridges. Flap dehiscence was observed in one case, which is recovered by mucosa after local treatment; 3 patients were observed with postoperative lower lip hypoesthesia, 1 of them combined with changed pulp sensitivity of the mandibular anterior teeth. After the use of mecobalamin, all lower lip hypoesthesia disappeared, while the mandibular anterior teeth's clinical symptoms improved. The follow-up period was 12 month to 30 month (mean 17.3 months). The survival rate of all 28 implants was 100%. Conclusions: By using autogenous block grafts from chin to improve the lack of bone mass in anterior maxilla, the results of ITI implants restore the loss of upper anterior teeth can be satisfied.%目的:探讨以颏部块状骨移植修复上颌前牙区骨量不足,二期行ITI种植术修复该区缺失牙的临床效果。方法:2009年7月~2012年5月间完成的上前牙区颏部块状骨移植后种植修复病例21例,平均年龄27.7岁(18~42岁)。单牙缺失14例,多牙缺失7例,共28枚种植体。结果:移植骨块愈合期平均6.3个月(4.5~10.0个月),种植体骨结合期平均5.2个月(3.5~9.0个月)。1

  15. 乳突尖部分切除加自体骨粉鼓室上壁重建在鼓室成形术中的应用%Mastoidale partial resection and superior tympanic wall reconstruction with autogenous bone meal in tympanoplasty

    Institute of Scientific and Technical Information of China (English)

    陈学华; 纪树芳; 李卡凡; 梅晓峰

    2013-01-01

    Objective To explore the value of mastoidale partial resection and superior tympanic wall reconstruction with autogenous bone meal in tympanoplasty. Methods A total of 42 patients with chronic suppurative otitis media (CSOM) were treated with open tympanoplasty. Among these patients,22 patients were treated with autologous bone hearing reconstruction (autologous bone group) and 20 patients were treated with titanium auricular bone reconstruction (titanium auricular bone group) . The dry ear rate,dry ear time,external auditory canal shape,hearing and complication were observed after operation in the two groups. Results The postauricular incisions of all patients in the two groups were primary healing,and there was no postoperative complications such as vertigo, facial nerve paralysis and tinnitus and tinnitus, etc. After operation, the mastoid cavity recovered with good epithelization, and without escharosis, otopiesis or adhesion. The dry ear rate in autologous bone group and titanium auricular bone group was 95.5% (21/22)and 95.0% (19/20) .respectively;there was no significant difference in dry ear rate between the two groups ( P > 0. 05 ). There was no significant difference in dry ear time between the two groups (P >0.05). Before treatment,there was no significant difference in air conduction auditory threshold and air-bone gap between the two groups (P >0. 05). The air conduction auditory threshold and air-bone gap after treatment were significantly lower than those before treatment in the two group(P <0. 05). After treatment, the air conduction auditory threshold and air-bone gap in titanium auricular bone group were significantly lower than those in autologous bone group (P < 0. 05). Conclusions Facial nerve monitoring can effectively identify the exposed facial nerve or thin bone canal facial nerve,and could avoid facial nerve injury during surgery. The mastoidale partial resection and superior tympanic wall reconstruction with autogenous bone meal

  16. Study of PRF Combined with Autogenous Bone Marrow Stem Cells on Alveolar Bone Defect%PRF复合自体骨髓间充质干细胞修复兔牙槽骨缺损的研究

    Institute of Scientific and Technical Information of China (English)

    张文丽; 李淑慧; 陈诚; 李一鸣; 周晶; 吴佩玲

    2015-01-01

    目的:观察富血小板纤维蛋白(platelet-rich fibrin,PRF)复合自体第3代骨髓间充质干细胞(bone marrow stem cells,BMSCs)修复牙槽骨缺损的能力.方法:取健康雄性2月龄新西兰兔36只,随机分为4组:PRF+BMSCs组、PRF组、BMSCs组、空白对照组,均在全麻下微创拔除下颌左侧中切牙.4组实验动物分别在4、8、12周处死.取其下颌骨进行牙槽骨标本测量,X线观察,组织学观察.结果:牙槽骨标本测量比较:4组牙槽嵴宽度、高度丧失值均存在差异(P<0.05);析因分析示PRF与BMSCs复合使用修复牙槽骨的效果优于单独使用PRF或BMSCs(P<0.05).X线、组织学观察表明术后4、8、12周时拔牙窝骨吸收程度:PRF+ BMSCs组<PRF组<BM-SCs组<空白对照组,PRF+ BMSCs组成骨情况均优于PRF组、BMSCs组、空白对照组.结论:PRF复合自体BMSCs可以促进牙槽骨的再生与修复,具有潜在的临床应用价值.

  17. Morphology of autogenous bone graft and castor oil polyurethane in the infraorbital rim of rabbits: a comparative study Estudo morfológico comparativo do enxerto ósseo autógeno e polímero de mamona em rebordo infra-orbitário de coelhos

    Directory of Open Access Journals (Sweden)

    José Carlos Garcia de Mendonça

    2006-10-01

    Full Text Available PURPOSE: Morphological study comparing castor oil polyurethane and autogenous bone graft to repair bone defect in zygomatic bone of rabbits. METHODS: Twenty-four adult, male New Zealand rabbits were randomly distributed between two groups of twelve. Bone defects of 5mm in diameter were cut through the zygomatic bone and filled with polyurethane discs in the experimental group or autogenous bone harvested from the tibia in the control group. Animals were sacrificed after 30, 60 or 90 days, and the zygomatic bones were macro- and microscopically analyzed. Student's, Fisher's, chi-squared and McNemar's tests were used for statistical analysis. RESULTS: Both the castor oil polyurethane and the autograft adapted well to the defect, with no need for fixation. Fibrous connective tissue encapsulated the polyurethane, but no inflammation or giant cell reaction was observed. Acidophilic and basophilic areas were observed inside the micropores of the polyurethane, suggesting cell nuclei. After 90 days, bone repair with a lamellar pattern of organization was observed in the control group. CONCLUSION: The castor oil polyurethane was biocompatible and did not cause inflammation. It may be considered an alternative to fill bone defects.OBJETIVO: Estudo morfológico comparativo do implante de poliuretana de mamona e enxerto ósseo autógeno em defeito ósseo padrão em osso zigomático de coelhos. MÉTODOS: Vinte e quatro coelhos Nova Zelândia, machos, adultos, foram distribuídos aleatoriamente em dois grupos de 12. Defeitos de 5mm de diâmetro, perenes, foram confeccionados em osso zigomático e preenchidos com discos pré-fabricados de poliuretana no grupo experimento ou osso autógeno extraído da tíbia no grupo controle. Os animais foram sacrificados após 30, 60 e 90 dias e as peças anatômicas foram avaliadas macro e microscopicamente. Foram utilizados os testes de Student, Fisher,qui-quadrado e McNemar para a análise estatística dos resultados

  18. Hard and Soft Tissue Management of a Localized Alveolar Ridge Atrophy with Autogenous Sources and Biomaterials: A Challenging Clinical Case

    Science.gov (United States)

    Andreoni, D.

    2016-01-01

    Particularly in the premaxillary area, the stability of hard and soft tissues plays a pivotal role in the success of the rehabilitation from both a functional and aesthetic aspect. The present case report describes the clinical management of a localized alveolar ridge atrophy in the area of the upper right canine associated with a thin gingival biotype with a lack of keratinized tissue. An autogenous bone block harvested from the chin associated with heterologous bone particles was used to replace the missing bone, allowing for a prosthetic driven implant placement. Soft tissues deficiency was corrected by means of a combined epithelialized and subepithelial connective tissue graft. The 3-year clinical and radiological follow-up demonstrated symmetric gingival levels of the upper canines, with physiological peri-implant probing depths and bone loss. Thus, the use of autogenous tissues combined with biomaterials might be considered a reliable technique in case of highly aesthetic demanding cases.

  19. Hard and Soft Tissue Management of a Localized Alveolar Ridge Atrophy with Autogenous Sources and Biomaterials: A Challenging Clinical Case

    Directory of Open Access Journals (Sweden)

    C. Maiorana

    2016-01-01

    Full Text Available Particularly in the premaxillary area, the stability of hard and soft tissues plays a pivotal role in the success of the rehabilitation from both a functional and aesthetic aspect. The present case report describes the clinical management of a localized alveolar ridge atrophy in the area of the upper right canine associated with a thin gingival biotype with a lack of keratinized tissue. An autogenous bone block harvested from the chin associated with heterologous bone particles was used to replace the missing bone, allowing for a prosthetic driven implant placement. Soft tissues deficiency was corrected by means of a combined epithelialized and subepithelial connective tissue graft. The 3-year clinical and radiological follow-up demonstrated symmetric gingival levels of the upper canines, with physiological peri-implant probing depths and bone loss. Thus, the use of autogenous tissues combined with biomaterials might be considered a reliable technique in case of highly aesthetic demanding cases.

  20. Autogenous Phenomena in Cement-Based Materials

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede

    Denne afhandling er skrevet med henblik på opnåelse af den danske doktorgrad i teknik, dr.techn. Den vedrører autogene fænomener i cementbaserede materialer – primært deformation og ændring af den relative luftfugtighed (RF). I afhandlingen er det belyst, hvordan betydningen af disse fænomener bl...

  1. 微型接骨板内固定结合自体松质骨移植治疗距骨颈粉碎性骨折%Open reduction and miniplate fixation with autogenous cancellous bone graft for comminuted talar neck fractures

    Institute of Scientific and Technical Information of China (English)

    魏世隽; 蔡贤华; 刘曦明; 陈家; 张志文; 汪波

    2013-01-01

    目的 探讨切开复位微型接骨板内固定结合自体松质骨移植治疗距骨颈粉碎性骨折的手术方法及疗效.方法 2010年1月~2012年1月,对我院收治的15例闭合性距骨颈粉碎性骨折患者,根据Hawkins分型:Ⅱ型11例,Ⅲ型4例.术前常规行CT三维重建明确骨折类型和粉碎程度,择期行切开复位微型接骨板内固定加自体松质骨移植术.术后定期复查X片及CT观察骨折愈合情况,并记录相关并发症,采用Hawkins评分标准评估疗效.结果 本组14例获得随访,随访时间12~24m,,平均16.4m.术后外侧切口边缘部分坏死1例,经局部清创换药后治愈,无并发感染,骨折均在8~12w内获得愈合,平均愈合时间11.3w,无畸形愈合发生,距骨体部分坏死1例(Ⅲ型),轻度创伤性关节炎3例(Ⅱ型1例,Ⅲ型2例),末次随访时未发现内固定松动断裂.Hawkins 评分:优7例(Ⅱ型),良5例(Ⅱ型4例,Ⅲ型1例),可2例(Ⅲ型).结论 采用切开复位微型接骨板内固定结合自体松质骨移植治疗距骨颈粉碎性骨折,术中可获得满意复位,牢靠的内固定可有效维持骨折复位,自体松质骨移植可促进骨折愈合,是治疗距骨颈粉碎性骨折的有效方法.%Objective To evaluate the surgical technique and clinical outcome of open reduction and miniplate fixation with autogenous cancellous bone graft for comminuted talar neck fractures.Method 15 patients with closed comminuted talar neck fractures were included between Jan 2010 and Jan 2012.According to Hawkins classification,11 cases were type Ⅱ fractures and 4 cases type Ⅲ fractures.All cases were evaluated carefully with X-ray and CT scan preoperatively to define the type and displacement of fractures.Open reduction and miniplate fixation with autogenous cancellous bone graft was performed until the swelling of soft tissue was vanished.The surgical wound healing was assessed after the surgery.X-ray and CT scan were taken in the follow

  2. Autogenic training as a therapy for adjustment disorder in adults

    OpenAIRE

    Jojić Boris R.; Leposavić Ljubica M.

    2005-01-01

    Introduction. Autogenic training is a widely recognised psychotherapy technique. The British School of Autogenic Training cites a large list of disorders, states, and changes, where autogenic training may prove to be of help. We wanted to explore the application of autogenic training as a therapy for adjustment disorder in adults. Our sample consisted of a homogeneous group of 35 individuals, with an average age of 39.3±1.6 years, who were diagnosed with adjustment disorder, F 43.2, in accord...

  3. Autogenic training as a therapy for adjustment disorder in adolescents

    OpenAIRE

    Jojić Boris R.; Leposavić Ljubica M.

    2005-01-01

    INTRODUCTION Autogenic training is a widespread technique used in psychotherapy. The British school of autogenic training cites a large list of diseases, health states, and life changes, in which autogenic training can be of help. We wanted to explore the application of autogenic training as a therapy for adjustment disorder in adolescents. The sample consisted of a homogeneous group of 31 individuals, with an average age of 17.3±0.2 years, who were diagnosed with adjustment disorder, F 43.2,...

  4. Local autogeneous bone grafts fusion in the treatment of lumbar spondylolisthesis%局部自体骨植骨融合治疗腰椎滑脱症临床体会

    Institute of Scientific and Technical Information of China (English)

    马维疆; 周丰华

    2011-01-01

    Objective Of posterior surgery in patients with spondylolisthesis local autologous bone implanted in the interbody and intertransverse fusion for the treatment experience.Methods 68patients with spondylolisthesis treated with posterior laminectomy bite addition to all of the spinous process,lamina,facet of autologous bone graft in the interbody and intertransverse fusion and pedicle screw fixation.Results 68 patients were followed up for 6 months to 7 years.Follow-up showed 67 patients were healed vertebral,clinical symptoms disappeared.One case without bone fusion.Satisfaction rate of 98.5%.Conclusions Posterior partial autologous bone graft surgery in interbody and intertransverse fusion for the treatment of spondylolisthesis is a really effective,simple,safe,less complications and low cost of surgical care.%目的 探讨腰椎滑脱症患者后路手术局部自体骨植于椎体间及横突间融合治疗效果.方法 对68例腰椎滑脱症患者采用后路全椎板减压咬除的棘突、椎板、关节突自体骨移植于椎体间及横突间融合加椎弓根钉系统固定.结果 68例均获随访,时间6月~7年.随访结果显示,67例患者椎体获骨性愈合,临床症状消失;1例未获骨性融合;满意率达98.5%.结论 后路手术局部自体骨移植于椎体间及横突间融合治疗腰椎滑脱症是一种疗效确实、具有操作简单、安全,并发症少、医疗费用低的术式.

  5. Autogenic training as a therapy for adjustment disorder in adolescents

    Directory of Open Access Journals (Sweden)

    Jojić Boris R.

    2005-01-01

    Full Text Available INTRODUCTION Autogenic training is a widespread technique used in psychotherapy. The British school of autogenic training cites a large list of diseases, health states, and life changes, in which autogenic training can be of help. We wanted to explore the application of autogenic training as a therapy for adjustment disorder in adolescents. The sample consisted of a homogeneous group of 31 individuals, with an average age of 17.3±0.2 years, who were diagnosed with adjustment disorder, F 43.2, in accordance with ICD 10 search criteria. OBJECTIVE The aim of our work was to figure out the influence of autogenic training on adjustment disorder, through biophysical and biochemical indicators, and to research the efficacy of autogenic training as a therapy for adjustment disorder in adolescents. METHOD We observed adjustment disorder indicators and their changes in three phases, using initial, final, and control values, which we measured immediately before the beginning, immediately after the completion, and six months after the completion, of the practical course in autogenic training. We measured systolic and diastolic arterial blood pressure, brachial pulse rates, cortisol levels in plasma, cholesterol levels in blood, as well as glucose concentrations. During that period, autogenic training was employed as the sole therapy. RESULTS The study confirmed our preliminary assumptions. The measurements we performed showed that arterial blood pressure, pulse rates, cholesterol and cortisol concentrations, after the application of autogenic training among adolescents suffering from adjustment disorder, were lower than the initial values. They remained lower even six months after the completion of the practical course in autogenic training. CONCLUSION We concluded that autogenic training significantly decreases the values of physiological indicators of adjustment disorder, diminishes the effects of stress in an individual, and eases the adaptation of

  6. Modelling autogenous expansion for magnesia concrete in arch dams

    Institute of Scientific and Technical Information of China (English)

    Feng JIN; Guoxin ZHANG; Xiaoqing LUO; Chuhan ZHANG

    2008-01-01

    Magnesia Concrete is a kind of expansive con-crete used in Chinese hydraulic engineering more and more widely. To evaluate the effects of autogenous expan-sion on the stresses of arch dams, a simple model of auto-genous expansion for Magnesia Concrete in dam engineering is presented. This model is based on three assumptions: 1) the total amount of autogenous expan-sion of Magnesia Concrete is related only to the properties of materials and mixing of concrete; 2) the autogenous expansion of Magnesia Concrete is irreversible due to the irreversibility of hydration reaction of Magnesia in the concrete; 3) the autogenous expansion strain rates of Magnesia Concrete bear a relation between temperature and residual Magnesia per unit volume of concrete. The model is verified by some experimental data of autogen-ous expansion of Magnesia Concrete and field-measured data of an arch dam in China. Embedded into finite ele-ment arch dam simulation software, this model is employed to simulate the effects of autogenous expansion of Magnesia Concrete in hydraulic engineering.

  7. Modeling and analyzing autogenous shrinkage of hardening cement paste

    NARCIS (Netherlands)

    Lu, T.; Koenders, E.A.B.

    2014-01-01

    In this paper, a conceptual model for analyzing the plastic part of autogenous deformation of cement paste based on the Arrhenius rate theory will be presented. The autogenous deformation will be calculated from the elastic deformations with inclusion of creep. Different kinds of cement paste with a

  8. 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.

  9. [Autogenic training in psychophysiological preparation for parachute jumps].

    Science.gov (United States)

    Reshetnikov, M M

    1978-01-01

    The efficiency of specific psychophysiological preparation--autogenic training--to parachute jumps was measured in two groups of cadets (test subjects and controls). Hetero- and autogenic training was carried out according to a scheme specially developed for this type of activity. The study of questionnaires and physiological data demonstrated that the specific psychophysiological preparation by means of autogenic training for a certain type of activity helped to develop active self-control over one's own state and emotions, alleviated tension, arrested adverse neurotic manifestations (sleep disturbances, depression, anxiety), contributed to the feeling of confidence in the successful completion of the jump and promoted positive tuning towards subsequent jumps.

  10. Olecranon bone graft: revisited.

    Science.gov (United States)

    Mersa, Berkan; Ozcelik, Ismail Bulent; Kabakas, Fatih; Sacak, Bulent; Aydin, Atakan

    2010-09-01

    Autogenous bone grafts are frequently in use in the field of reconstructive upper extremity surgery. Cancellous bone grafts are applied to traumatic osseous defects, nonunions, defects after the resection of benign bone tumors, arthrodesis, and osteotomy procedures. Cancellous bone grafts do not only have benefits such as rapid revascularization, but they also have mechanical advantages. Despite the proximity to the primary surgical field, cancellous olecranon grafts have not gained the popularity they deserve in the field of reconstructive hand surgery. In this study, the properties, advantages, and technical details of harvesting cancellous olecranon grafts are discussed.

  11. Effects of a buried magnetic field on cranial bone reconstruction in rats

    Science.gov (United States)

    de ABREU, Maíra Cavallet; PONZONI, Deise; LANGIE, Renan; ARTUZI, Felipe Ernesto; PURICELLI, Edela

    2016-01-01

    ABSTRACT The understanding of bone repair phenomena is a fundamental part of dentistry and maxillofacial surgery. Objective The present study aimed to evaluate the influence of buried magnetic field stimulation on bone repair in rat calvaria after reconstruction with autogenous bone grafts, synthetic powdered hydroxyapatite, or allogeneic cartilage grafts, with or without exposure to magnetic stimulation. Material and Methods Ninety male Wistar rats were divided into 18 groups of five animals each. Critical bone defects were created in the rats’ calvaria and immediately reconstructed with autogenous bone, powdered synthetic hydroxyapatite or allogeneic cartilage. Magnetic implants were also placed in half the animals. Rats were euthanized for analysis at 15, 30, and 60 postoperative days. Histomorphometric analyses of the quantity of bone repair were performed at all times. Results These analyses showed significant group by postoperative time interactions (p=0.008). Among the rats subjected to autogenous bone reconstruction, those exposed to magnetic stimulation had higher bone fill percentages than those without magnetic implants. Results also showed that the quality of bone repair remained higher in the former group as compared to the latter at 60 postoperative days. Conclusions After 60 postoperative days, bone repair was greater in the group treated with autogenous bone grafts and exposed to a magnetic field, and bone repair was most pronounced in animals treated with autogenous bone grafts, followed by those treated with powdered synthetic hydroxyapatite and allogeneic cartilage grafts. PMID:27119765

  12. Morbidity from iliac crest bone harvesting

    NARCIS (Netherlands)

    Kalk, WWI; Raghoebar, GM; Jansma, J; Boering, G

    1996-01-01

    Purpose: The iliac crest is the most common donor site for autogenous bone grafting in maxillofacial surgery. The aim of this study was to evaluate retrospectively the morbidity of bone harvesting from the inner table of the anterior iliac crest. Patients and Methods: Sixty-five patients were recall

  13. Bone Marrow Concentrate and Bovine Bone Mineral for Sinus Floor Augmentation : A Controlled, Randomized, Single-Blinded Clinical and Histological Trial-Per-Protocol Analysis

    NARCIS (Netherlands)

    Sauerbier, Sebastian; Rickert, Daniela; Gutwald, Ralf; Nagursky, Heiner; Oshima, Toshiyuki; Xavier, Samuel P.; Christmann, Johannes; Kurz, Patrick; Menne, Dieter; Vissink, Arjan; Raghoebar, Gerry; Schmelzeisen, Rainer; Wagner, Wilfried; Koch, Felix P.

    2011-01-01

    Purpose: The purpose of this work was to evaluate the potential of substituting autogenous bone (AB) by bone marrow aspirate concentrate (BMAC). Both AB and BMAC were tested in combination with a bovine bone mineral (BBM) for their ability of new bone formation (NBF) in a multicentric, randomized, c

  14. Reimplantation of cultivated human bone cells from the posterior maxilla for sinus floor augmentation

    DEFF Research Database (Denmark)

    Hermund, Niels Ulrich; Stavropoulos, Andreas; Donatsky, Ole

    2012-01-01

    OBJECTIVES: The aim of the present randomized clinical study was to evaluate histologically whether the addition of cultivated, autogenous bone cells to a composite graft of deproteinized bovine bone mineral (DBBM) and autogenous bone (AB) for sinus floor augmentation (SFA) enhance bone formation...... bone cells, which were cultivated from a bone biopsy harvested earlier from the tuberosity area. Four months after SFA, two cylindrical biopsies were taken from the augmented sinuses concomitantly with the implant site preparation by means of a trephine bur. An additional biopsy was taken from...... groups, respectively. Bone augmentation height averaged 6.0 and 5.4 mm and RBD averaged 0.48 and 0.73 in the cell seeded and no-cells added DBBM + AB groups, respectively. None of the differences between groups was statistically significant. CONCLUSIONS: Cultivated autogenous bone cell seeded to a DBBM...

  15. Estimulação da cicatrização óssea pelo plasma autógeno rico em plaquetas: estudo experimental em coelhos Bone healing stimulation by platelet-rich autogenous plasma: an experimental study in rabbits

    Directory of Open Access Journals (Sweden)

    Elisabete Mitiko Kobaiashi Wilson

    2006-01-01

    Full Text Available O plasma sangüíneo autógeno com alta concentração de plaquetas obtido por centrifugação (plasma rico em plaquetas, ou PRP tem sido utilizado na prática clínica para estimular a cicatrização óssea numa variedade de situações, sob alegação de que ele carrega uma elevada concentração de fatores de crescimento derivados da plaqueta e beta-transformadores, os quais sabidamente estimulam o crescimento e regeneração de diferentes tecidos. No presente estudo, o PRP foi utilizado para reparar uma falha óssea diafisária segmentar de meia espessura e 2 cm de comprimento produzida no radio de coelhos Nova Zelândia. O periósteo foi ressecado na circunferência do local da falha e a cavidade medular foi selada com cera óssea em todos os animais para bloquear a chegada de celular regeneradoras que não fossem do próprio osso, mas dos tecidos vizinhos. Três grupos de 15 animais cada foram planejados, de acordo com o procedimento realizado: 1 falha deixada vazia; 2 falha preenchida com o PRP; e 3 falha preenchida com um material inerte (Gelfoam®. Em cada grupo os animais foram distribuídos em três subgrupos de acordo com o período de observação pós-operatória, de 4, 8 e 12 semanas, respectivamente, depois do qual os animais foram mortos e o radio, ressecado para os estudos histológicos. Radiografias e cintilografias foram obtidas a intervalos de 4 semanas, começando na quarta semana pós-operatória. Cicatrização completa e remodelação foram observadas no grupo 2 já na 8ª semana, enquanto que nos grupos 1 e 3 esse processo era apenas parcial na 12ª. A captação do tecnécio estava aumentada em todos os grupos, assim permanecendo durante todo o período de observação nos grupos 1 e 3, mas diminuindo da 8ª para a 12ª semana no grupo 2, acompanhando o processo de remodelação, com diferenças significantes entre os grupos (pThe autogenous blood plasma with high platelet concentration obtained through centrifugation

  16. Evaluation of “Autogenous Bioengineered Injectable PRF – Tooth graft” combination (ABIT in reconstruction of maxillary alveolar ridge defects: CBCT volumetric analysis

    Directory of Open Access Journals (Sweden)

    Lydia Nabil Melek

    2017-01-01

    Full Text Available Background: Extracted human teeth were suggested as a source for autogenous bone grafts, especially that they have similar chemical composition to bone. In order to accelerate healing of bone graft over the bony defect, numerous techniques utilizing platelet and fibrinogen concentrations have been introduced in the literature. Objectives: To evaluate clinically and radiographically the use of autogenous tooth bone graft material in combination with injectable platelet-rich fibrin for reconstruction of resorbed maxillary alveolar ridge. Patients and methods: This study was conducted in ten patients indicated for extraction of maxillary anterior or premolar teeth and having maxillary ridge deficiency. Implants were placed after a period of 3 months of bone grafting. The patients were selected from those attending the Oral and Maxillofacial Surgery Department, Faculty of Dentistry, Alexandria University. Results: Clinically, all the patients showed uneventful healing. Radiographically, the results show 30% increase in mean bone density in the period of six months when compared to pre-operative readings. The grafted site showed an increase in the mean volume by 23.47% three months post-operative when compared to the base line measurements preoperatively. Radiographic evaluation of the alveolar ridge after 3 months of grafting showed a significant mean increase in the ridge width and height at the grafted site. Conclusion: Autogenous fresh demineralized tooth graft that is prepared at the chairside after extractions could be considered as the gold standard for socket preservation, bone augmentation in sinuses or filling bone defects, in patients having non restorable teeth indicated for extraction. The adjuvant use of injectable PRF with its high growth factor content may contribute to more favorable and predictable bone formation at the grafted site.

  17. Basin Depth Control on the Autogenic Timescale of Fluviodeltaic Systems

    Science.gov (United States)

    Carlson, B.; Kim, W.; Piliouras, A.

    2013-12-01

    ABSTRACT Autogenic processes are inherent processes in sediment transport that influence landscape building and leave distinct signatures in the sedimentary record. It is of great interest to understand autogenic processes in order to decouple internal processes from external controls, such as tectonics or climate change. Here we present results from a series of delta-building experiments to determine the variability of the fluviodeltaic autogenic timescale in response to varying basin water depth. This internal timescale was measured as the time that is required for the delta topset to be reworked through a full cycle of storage and release of sediment. The topset aggrades by fluvial sedimentation until it reaches a maximum slope, at which point a large amount of sediment starts to release, typically resulting in strong channelization. This is followed by a period of avulsions, lateral migration, and backfilling of channels on the topset. These storage and release events are repeated. We used time-lapse images to track shoreline positions and observe changes in progradation rate. The changes in topset topography were also used to determine storage and release duration. The experimental results indicate that the autogenic timescales generally increase with increasing basin water depth. These observations may be explained by the amount of time required to build a lobe with an area large enough to trigger a switch from a lobe-building release event to a backfilling storage event. Individual lobes show a similar surface area regardless of basin depth in the experiments. Deeper basin depth simply requires a larger volume to be filled within this area, thus more time to complete one autogenic process. However, when channel depth is significantly smaller than basin depth, e.g., in very deep basins, stochastic variability in sediment transport and channel lateral mobility outweighs the autogenic cyclicity. This study suggests that internal dynamics and its stratigraphic

  18. Measuring techniques for autogenous strain of cement paste

    DEFF Research Database (Denmark)

    Lura, Pietro; Jensen, Ole Mejlhede

    2006-01-01

    Volumetric measurement of autogenous strain is frequently performed by placing the fresh cement paste in a rubber membrane submerged in water. The volume change of the cement paste is measured by the amount of water displaced by the submerged sample. Volumetric and linear measurements of autogenous...... of the volumetric method. Water absorption is driven by a lowering of the water activity in the cement paste due to dissolved salts in the pore fluid and to self-desiccation. From the moment of casting, significant water uptake was registered in all experiments. This water uptake influenced the volumetric...... on the same cement pastes....

  19. Measuring techniques for autogenous strain of cement paste

    DEFF Research Database (Denmark)

    Lura, Pietro; Jensen, Ole Mejlhede

    2007-01-01

    Volumetric measurement of autogenous strain is frequently performed by placing the fresh cement paste in a rubber membrane submerged in water. The volume change of the cement paste is measured by the amount of water displaced by the submerged sample. Volumetric and linear measurements of autogenous...... of the volumetric method. Water absorption is driven by a lowering of the water activity in the cement paste due to dissolved salts in the pore fluid and to self-desiccation. From the moment of casting, significant water uptake was registered in all experiments. This water uptake influenced the volumetric...... on the same cement pastes....

  20. Team management of atrophic edentulism with autogenous inlay, veneer, and split grafts and endosseous implants: case reports.

    Science.gov (United States)

    Collins, T A; Brown, G K; Johnson, N; Massey, J A; Nunn, B D

    1995-02-01

    Predictable success of autogenous graft and implant reconstructions is critically dependent on preoperative alignment and prosthetic considerations planned by the surgeon and the restorative dentist in a team approach. In such cases the surgeon has an opportunity to place accurate bone grafts that allow implants to be secured in both the correct position and correct axis for good prosthetic restoration. With careful thought, the restorative dentist and surgeon can plan the location, shape, and volume of an implant-graft reconstruction. Nine requirements for successful onlay grating with implants and five case reports illustrating the team approach are presented.

  1. Guided bone regeneration with local zoledronic acid and titanium barrier: An experimental study

    Science.gov (United States)

    Dundar, Serkan; Ozgur, Cem; Yaman, Ferhan; Cakmak, Omer; Saybak, Arif; Ozercan, Ibrahim Hanifi; Alan, Hilal; Artas, Gokhan; Nacakgedigi, Onur

    2016-01-01

    The aim of this study was to evaluate the effects on new bone formation of autogenous blood alone or in combination with zoledronic acid (ZA), a β-tricalcium phosphate (β-TCP) graft or ZA plus a β-TCP graft placed under titanium barriers. For this purpose, eight adult male New Zealand white rabbits were used in the study, each with four titanium barriers fixed around four sets of nine holes drilled in the calvarial bones. The study included four groups, each containing 2 rabbits. In the autogenous blood (AB group), only autogeneous blood was placed under the titanium barriers. The three experimental groups were the AB+ZA group, with autogenous blood plus ZA, the AB+β-TCP group, with autogeneous blood plus a β-TCP graft, and the AB+β-TCP+ZA group, with autogeneous blood plus a β-TCP graft and ZA mixture under the titanium barriers. The animals were sacrificed after 3 months. The amounts of new bone formation identified histomorphometrically were found to be higher after 3 months than at the time of surgery in all groups. The differences between the groups were examined with histomorphometric analysis, and statistically significant differences were identified at the end of the 3 months. The bone formation rate in the AB+β-TCP+ZA group was determined to be significantly higher than that in the other groups (P<0.05). In the AB+ZA and AB+β-TCP groups, the bone formation rate was determined to be significantly higher than that in the AB group (P<0.05). No statistically significant difference in bone formation rate was observed between the AB+β-TCP and AB+ZA groups. Local ZA used with autogeneous blood and/or graft material appears to be a more effective method than the use of autogeneous blood or graft alone in bone augmentation executed with a titanium barrier. PMID:27698687

  2. Measuring autogenous strain of concrete with corrugated moulds

    DEFF Research Database (Denmark)

    Tian, Qian; Jensen, Ole Mejlhede

    2008-01-01

    A reliable technique to quantify autogenous strain is a prerequisite to numerical modeling in stress calculations for high performance concrete. The introducing of a special kind of corrugated tube mould helps to transforming volume strain measurement into liner strain measurement in horizontal...

  3. Thermodynamics of Autogenous Self-healing in Cementitious Materials

    NARCIS (Netherlands)

    Huang, H.

    2014-01-01

    Concrete is a brittle composite cementitious material that easily fractures under tensile loading. Microcracks can appear throughout the concrete prior to application of any load because of temperature-induced strain and autogenous and drying shrinkage. There is no doubt that these cracks provide pr

  4. 30 CFR 35.20 - Autogenous-ignition temperature test.

    Science.gov (United States)

    2010-07-01

    ...-constantan or chromelalumel—and a potentiometer shall be used for all temperature measurements. (3) Syringe...) Temperature control. Each autotransformer shall be so adjusted that the temperature at the neck, mid-section... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Autogenous-ignition temperature test....

  5. Autogeneous healing and chloride ingress in cracked concrete

    NARCIS (Netherlands)

    Savija, B.; Schlangen, E.

    2016-01-01

    An experimental study of the influence of autogeneous healing on chloride ingress in cracked concrete is presented. In the study, two concrete mixtures (a Portland cement mix and a blast furnace slag mix), two healing regimes (submerged and fog room regime), two cracking ages (14 and 28 days), and m

  6. Cracking in cement paste induced by autogenous shrinkage

    DEFF Research Database (Denmark)

    Lura, Pietro; Jensen, Ole Mejlhede; Weiss, Jason

    2009-01-01

    technique allows identification of microcracks while avoiding artefacts induced by unwanted restraint, drying, or temperature variations during sample preparation. Small cylindrical samples of cement paste are cast with steel rods of different diameters in their centre. The rods restrain the autogenous...

  7. Autogenic training: a narrative and quantitative review of clinical outcome.

    Science.gov (United States)

    Linden, W

    1994-09-01

    This review of controlled outcome research on Autogenic Training complements the literature by pooling narrative and quantitative approaches, by including only studies with experimental controls, by integrating the English and German literature, and by adding research findings published since the last review. Whereas previous reviews have already reported positive effects of Autogenic Training for migraine, insomnia, and test anxiety, additional supportive findings for angina pectoris, asthma, childbirth, eczema, hypertension, infertility, Raynaud's disease, and recovery from myocardial infarction are discussed here. The impact of protocol variations on outcome is described, and the specificity of Autogenic Training relative to other stress management techniques is highlighted. Quantitative findings suggested that Autogenic Training was associated with medium-sized pre- to posttreatment effects ranging from d = .43 for biological indices of change to d = .58 for psychological and behavioral indices thus matching effect sizes for other biobehavioral treatment techniques like biofeedback and muscular relaxation. Length of treatment did not affect clinical outcome. The discussion emphasizes how narrative and quantitative strategies complement one another.

  8. Treatment of Childhood Migraine Using Autogenic Feedback Training.

    Science.gov (United States)

    Labbe, Elise L.

    1984-01-01

    Compared autogenic feedback training with a waiting-list control group as a treatment for children (N=28) with migraine headaches. Children in the treatment condition were significantly improved at the end of treatment and at one-month and six-month follow-up. No improvement was found for the children in the control condition. (BH)

  9. Análise por tomografia computadorizada do enxerto autógeno na cirurgia de "sinus lift" Computed tomography evaluation of autogenous graft in sinus lift surgery

    Directory of Open Access Journals (Sweden)

    Sérgio Aron Ajzen

    2005-02-01

    Full Text Available OBJETIVO: Quantificar a formação óssea nos enxertos com e sem plasma rico em plaquetas, obtido pelos métodos de centrifugação e aférese, comparando os três tipos de enxertos realizados por meio de análise tomográfica. MATERIAIS E MÉTODOS: Este estudo prospectivo, duplo cego, utilizou uma amostra composta de 34 pacientes adultos, de ambos os sexos, com idade média de 48 anos e 8 meses, portadores de pneumatização unilateral ou bilateral dos seios maxilares, que necessitavam de enxertos ósseos, com a finalidade de melhorar as condições locais para a colocação dos implantes dentários. Todos os pacientes realizaram tomografia computadorizada antes da cirurgia. Foram operados 53 seios maxilares, divididos em três grupos: enxerto de plasma rico em plaquetas obtido pelos métodos de aférese, centrifugação e enxerto apenas de osso autógeno. Após seis meses do procedimento cirúrgico foram realizados novos exames de imagem. RESULTADOS: Pela avaliação tomográfica, houve crescimento em altura e em largura nos três grupos quando foram comparados os momentos inicial e final, entretanto, não houve diferença estatística para a altura e para a largura. CONCLUSÃO: Evidências clínicas demonstram a eficácia dos enxertos autógenos, principalmente os associados a fatores indutores de crescimento ósseo, como o plasma rico em plaquetas, recuperando o arcabouço maxilofacial, necessário para a reconstrução protética e funcional por meio de implantes dentários.OBJECTIVE: To quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from aphaeresis or centrifugation using computed tomography. MATERIALS AND METHODS: This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months, with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental

  10. Autogenous tooth transplantation for replacing a lost tooth: case reports

    OpenAIRE

    Kang, Ji-Youn; Chang, Hoon-Sang; Hwang,Yun-Chan; Hwang, In-Nam; Oh, Won-Mann; LEE, Bin-Na

    2013-01-01

    The autogenous tooth transplantation is an alternative treatment replacing a missing tooth when a suitable donor tooth is available. It is also a successful treatment option to save significant amount of time and cost comparing implants or conventional prosthetics. These cases, which required single tooth extraction due to deep caries and severe periodontal disease, could have good results by transplanting non-functional but sound donor tooth to the extraction site.

  11. Immunolocalization of markers for bone formation during guided bone regeneration in osteopenic rats

    Directory of Open Access Journals (Sweden)

    Tábata de Mello TERA

    2014-12-01

    Full Text Available Objective The aim of this paper was to evaluate the repair of onlay autogenous bone grafts covered or not covered by an expanded polytetrafluoroethylene (e-PTFE membrane using immunohistochemistry in rats with induced estrogen deficiency. Material and Methods Eighty female rats were randomly divided into two groups: ovariectomized (OVX and with a simulation of the surgical procedure (SHAM. Each of these groups was again divided into groups with either placement of an autogenous bone graft alone (BG or an autogenous bone graft associated with an e-PTFE membrane (BGM. Animals were euthanized on days 0, 7, 21, 45, and 60. The specimens were subjected to immunohistochemistry for bone sialoprotein (BSP, osteonectin (ONC, and osteocalcin (OCC. Results All groups (OVX+BG, OVX+BMG, SHAM+BG, and SHAM+BMG showed greater bone formation, observed between 7 and 21 days, when BSP and ONC staining were more intense. At the 45-day, the bone graft showed direct bonding to the recipient bed in all specimens. The ONC and OCC showed more expressed in granulation tissue, in the membrane groups, independently of estrogen deficiency. Conclusions The expression of bone forming markers was not negatively influenced by estrogen deficiency. However, the markers could be influenced by the presence of the e-PTFE membrane.

  12. Alveolar ridge preservation using autogenous tooth graft versus beta-tricalcium phosphate alloplast: A randomized, controlled, prospective, clinical pilot study

    Directory of Open Access Journals (Sweden)

    Chaitanya Pradeep Joshi

    2016-01-01

    Full Text Available Background: A randomized, prospective clinical, radiographical, and histological study was conducted to evaluate healing after alveolar ridge preservation technique using two different graft materials, namely, a novel autogenous graft material i. e., autogenous tooth graft (ATG and beta-tricalcium phosphate (β-TCP alloplast. Materials and Methods: Fifteen patients undergoing extraction of at least three teeth were selected. Atraumatic extractions were performed. Of the three extraction sockets, one was grafted with ATG, other with β-TCP, and the third was left ungrafted. Cone-beam computed tomography scans were taken immediately after grafting and 4 months postoperatively to check the changes in alveolar crest height and width at all the sites. Three patients in whom implant placement was done after complete healing; bone samples were harvested using a 3 mm diameter trephine during osteotomy preparation from both the ridge preserved sites and studied histologically. Results: There was a statistically significant difference when the changes in width and height of alveolar crest were compared within all the three groups (P < 0.05. Among three sites, ATG-grafted sites showed the most superior results with a minimal reduction in alveolar crest height and width. Histological analysis also showed the same trend with more new bone formation at ATG-grafted sites as compared to β-TCP-grafted sites. Conclusion: Postextraction, ridge preservation leads to more predictable maintenance of alveolar ridge height and width. ATG as compared to β-TCP provided superior results. Based on this, we conclude that ATG material can serve as a better alternative to conventional bone graft materials.

  13. Autogenous Regulation of Splicing of the Transcript of a Yeast Ribosomal Protein Gene

    Science.gov (United States)

    Dabeva, Mariana D.; Post-Beittenmiller, Martha A.; Warner, Jonathan R.

    1986-08-01

    The gene for a yeast ribosomal protein, RPL32, contains a single intron. The product of this gene appears to participate in feedback control of the splicing of the intron from the transcript. This autogenous regulation of splicing provides a striking analogy to the autogenous regulation of translation of ribosomal proteins in Escherichia coli.

  14. Autogenous shrinkage in high-performance cement paste: An evaluation of basic mechanisms

    DEFF Research Database (Denmark)

    Lura, Pietro; Jensen, Ole Mejlhede; van Breugel, Klaas

    2003-01-01

    In this paper, various mechanisms Suggested to cause autogenous shrinkage are presented. The mechanisms are evaluated from the point of view of their soundness and applicability to quantitative modeling of autogenous shrinkage. The capillary tension approach is advantageous, because it has a soun...

  15. Influence of temperature on autogenous deformation and relative humidity change in hardening cement paste

    DEFF Research Database (Denmark)

    Jensen, Ole Mejlhede; Hansen, Per Freiesleben

    1999-01-01

    This paper deals with autogenous deformation and autogenous relative humidity change (RH change) in hardening cement paste. Theoretical considerations and experimental data are presented, which elucidate the influence of temperature on these properties. This is an important subject in the control...

  16. Adjuvant auricular electroacupuncture and autogenic training in rheumatoid arthritis: a randomized controlled trial. Auricular acupuncture and autogenic training in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Bernateck, M; Becker, M; Schwake, C

    2008-01-01

    BACKGROUND: In contrast to psychological interventions the usefulness of acupuncture as an adjuvant therapy in rheumatoid arthritis (RA) has not yet been demonstrated. OBJECTIVE: The efficacy of auricular electroacupuncture (EA) was directly compared with autogenic training (AT). METHODS: Patients...

  17. Autogenic therapy: Techniques, foundations, health and clinical applications, and empirical support

    Directory of Open Access Journals (Sweden)

    Manuel R. Abuín

    2016-12-01

    Full Text Available Autogenic therapy emerges from the "autogenic training" method created by Schultz, and its development incorporates different therapeutic methods based on a psychophysiological approach. All these methods promote homeostatic self-regulatory brain processes. The aims of this paper are to describe and analyse the autogenic methods, the psychophysiological and neurophysiological processes involved, and their effective applications in both health and clinical fields. For these purposes, beside reviewing the earlier work by Schultz and Luthe, an electronic search of literature was conducted in order to find relevant contributions on these topics. Results show a big development of autogenic methods until the 80s, with an enormous amount of applications and studies on the psychophysiological and neurophysiological changes related to the practice of autogenic training. However, their expansion during the last 25 years has been much lower in comparison with other methods such as mindfulness and hypnosis. Possible causes are discussed and new challenges are suggested

  18. Autogenous electrolyte, non-pyrolytically produced solid capacitor structure

    Science.gov (United States)

    Sharp, D.J.; Armstrong, P.S.; Panitz, J.K.G.

    1998-03-17

    A solid electrolytic capacitor is described having a solid electrolyte comprising manganese dioxide dispersed in an aromatic polyamide capable of further cure to form polyimide linkages, the solid electrolyte being disposed between a first electrode made of valve metal covered by an anodic oxide film and a second electrode opposite the first electrode. The electrolyte autogenously produces water, oxygen, and hydroxyl groups which act as healing substances and is not itself produced pyrolytically. Reduction of the manganese dioxide and the water molecules released by formation of imide linkages result in substantially improved self-healing of anodic dielectric layer defects. 2 figs.

  19. Autogenic-feedback training: A countermeasure for orthostatic intolerance

    Science.gov (United States)

    Cowings, Patricia S.; Toscano, William B.; Kamiya, Joe; Miller, Neal E.; Pickering, Thomas G.

    1991-01-01

    NASA has identified cardiovascular deconditioning as a serious biomedical problem associated with long-duration exposure to microgravity in space. High priority has been given to the development of countermeasures for this disorder and the resulting orthostatic intolerance experienced by crewmembers upon their return to the 1g norm of Earth. The present study was designed to examine the feasibility of training human subjects to control their own cardiovascular responses to gravitational stimulation (i.e., a tilt table). Using an operant conditioning procedure, Autogenic-Feedback Training (AFT), we would determine if subjects could learn to increase their own blood pressure voluntarily.

  20. Maxillary bone grafting for insertion of endosseous implants : results after 12-124 months

    NARCIS (Netherlands)

    Raghoebar, GM; Timmenga, NM; Reintsema, H; Stegenga, B; Vissink, A

    2001-01-01

    Insertion of endosseous implants in the atrophic maxilla is often complicated because of lack of supporting bone. Augmentation of the floor of the maxillary sinus with autogenous bone graft has been proven to be a reliable treatment modality, at least in the short term. The long-term clinical and ra

  1. Bone replacement following dental trauma prior to implant surgery - present status

    NARCIS (Netherlands)

    Hallman, Mats; Mordenfeld, Arne; Strandkvist, Tomas

    2009-01-01

    Dento-alveolar trauma often leads to a need for reconstruction of the alveolar crest before an implant can be placed. Although autogenous bone grafts is considered the 'gold standard', this may be associated with patient morbidity and graft resorption. Consequently, the use of bone substitutes has i

  2. Progress in Using Free Autogenous Periosteal Grafts to Repair Articular Cartilage Defects%自体游离骨膜移植修复关节软骨缺损的研究进展

    Institute of Scientific and Technical Information of China (English)

    禹克俊

    2009-01-01

    The cambium layer of Periosteum contains undifferentiated mesenchymal cells, which have the duality into cartilage and into bone. The low tension hypoxia of articular cavity is good for the process, that periosteal becoming to cartilage, but free autologous periosteal graft to repairing articular cartilage defects is still in the exploratory stage, this article is a brief overview on the status quo of autogenous free periosteal graft repairing articular cartilage defects.

  3. Effectiveness of two regeneration materials in autogenous tooth transplantation in larger sockets:an experimental study in beagle dogs

    Institute of Scientific and Technical Information of China (English)

    Samjhana Kashaju; Yarning Chen; Ting Chen

    2008-01-01

    Objective:To evaluate the effectiveness of regenerous tissue and bone substitute in autogenous tooth transplantation in the larger recipient socket. Methods:In 3 Beagle dogs, 18 incisors were transplanted to the recipient sockets, 2 mm wider mesio-distally. The regenerous tissue group, the bone substitute group and the control group contained 7, 7 and 4 teeth respectively. No additional material was used in control group. Clinical and radiographic examinations were done every month and were sacrificed 3 months later. Subsequently, decalcified sections were prepared for routine histological evaluation. Ordinal scores for root surface resorption were analyzed using the Kruskal-Wallis test. Results:All donor teeth survived. A statistically significant difference was found among.all three treatment groups(P=0.0001). The proliferating tissue in space positively affected the periodontal healing without any resorption. Inflammatory resorption of the root surface and formation of new bone were observed in the bone substitute group. Surface resorptions of the roots were found in the control group. Conclusion:Proliferating tissues enhance the regeneration of periodontal tissues in larger recipient sockets and prevent root resorption. Sinbone HT is beneficial for the stabilization of the transplanted teeth in larger sockets.

  4. Osteogenic Matrix Cell Sheets Facilitate Osteogenesis in Irradiated Rat Bone

    Directory of Open Access Journals (Sweden)

    Yoshinobu Uchihara

    2015-01-01

    Full Text Available Reconstruction of large bone defects after resection of malignant musculoskeletal tumors is a significant challenge in orthopedic surgery. Extracorporeal autogenous irradiated bone grafting is a treatment option for bone reconstruction. However, nonunion often occurs because the osteogenic capacity is lost by irradiation. In the present study, we established an autogenous irradiated bone graft model in the rat femur to assess whether osteogenic matrix cell sheets improve osteogenesis of the irradiated bone. Osteogenic matrix cell sheets were prepared from bone marrow-derived stromal cells and co-transplanted with irradiated bone. X-ray images at 4 weeks after transplantation showed bridging callus formation around the irradiated bone. Micro-computed tomography images at 12 weeks postoperatively showed abundant callus formation in the whole circumference of the irradiated bone. Histology showed bone union between the irradiated bone and host femur. Mechanical testing showed that the failure force at the irradiated bone site was significantly higher than in the control group. Our study indicates that osteogenic matrix cell sheet transplantation might be a powerful method to facilitate osteogenesis in irradiated bones, which may become a treatment option for reconstruction of bone defects after resection of malignant musculoskeletal tumors.

  5. 自体髂骨与胶原-羟基磷灰石复合重组人骨形成蛋白2修复大鼠单侧腭裂%Autogenous iliac boneversuscollagen/hydroxyapatite/recombinant human bone morphogenetic protein-2 composite material for repair of unilateral cleft palate in rats

    Institute of Scientific and Technical Information of China (English)

    沈悦; 马海英; 张彦升; 王娟; 时炳正

    2015-01-01

      结果与结论:随时间的推移,碱性磷酸酶活性逐渐升高,抗酒石酸酸性磷酸酶活性逐渐降低,实验组碱性磷酸酶活性始终高于对照组(P OBJECTIVE:To detect the healing effect of autologous bone graft versus colagen/hydroxyapatite/recombinant human bone morphogenetic protein-2 composite graft in a rat model of unilateral complete cleft palate. METHODS: Firstly, we established the artificial unilateral complete cleft palate models in 32 Sprague-Dawley rats, and then the established animal models were randomly divided into control group and experimental group. The autologous iliac bone was transplanted into the fissures of control group, and the experimental group received colagen/hydroxyapatite/recombinant human bone morphogenetic protein-2 composite graft. After that, the activities of serum alkaline phosphatase and tartrate-resistant acid phosphatase, bone mineral densities in the neonatal palate, expressions of osteocalcin, osteoprotegerin, core binding factor, and osteoclast differentiation factor were detected at 1, 2, 3, 4 weeks after treatment. RESULTS AND CONCLUSION: Over time, the alkaline phosphatase activity increased gradualy, while tartrate-resistant acid phosphatase activity decreased. Compared with the control group, the alkaline phosphatase activity was always higher (P < 0.05,P < 0.01) but the tartrate-resistant acid phosphatase activity was lower in the experimental group (P < 0.05,P < 0.01); the bone mineral density increased in both groups, but it was always higher in the experimental group than the control group (P < 0.01). The expression levels of osteocalcin, osteoprotegerin, and core-binding factor gene gradualy rose in both groups, but they were always higher in the experimental group than the control group; in contrast, the expression of osteoclast differentiation factor was decreased in both groups, and it was lower in the experimental group than the control group. These findings indicate that

  6. Autogenic reaction synthesis of photocatalysts for solar fuel generation

    Energy Technology Data Exchange (ETDEWEB)

    Ingram, Brian J.; Pol, Vilas G.; Cronauer, Donald C.; Ramanathan, Muruganathan

    2016-04-19

    In one preferred embodiment, a photocatalyst for conversion of carbon dioxide and water to a hydrocarbon and oxygen comprises at least one nanoparticulate metal or metal oxide material that is substantially free of a carbon coating, prepared by heating a metal-containing precursor compound in a sealed reactor under a pressure autogenically generated by dissociation of the precursor material in the sealed reactor at a temperature of at least about 600.degree. C. to form a nanoparticulate carbon-coated metal or metal oxide material, and subsequently substantially removing the carbon coating. The precursor material comprises a solid, solvent-free salt comprising a metal ion and at least one thermally decomposable carbon- and oxygen-containing counter-ion, and the metal of the salt is selected from the group consisting of Mn, Ti, Sn, V, Fe, Zn, Zr, Mo, Nb, W, Eu, La, Ce, In, and Si.

  7. Autogenous Shrinkage of High Strength Lightweight Aggregate Concrete

    Institute of Scientific and Technical Information of China (English)

    DING Qingjun; TIAN Yaogang; WANG Fazhou; ZHANG Feng; HU Shuguang

    2005-01-01

    The characteristic of autogenous shrinkage ( AS ) and its effect on high strength lightweight aggregate concrete (HSLAC) were studied. The experimental results show that the main shrinkage of high strength concrete is AS and the amount of cement can affect the AS of HSLAC remarkably. At the early stage the AS of HSLAC is lower than that of high strength normal concrete, but it has a large growth at the later stage. The AS of high strength normal concrete becomes stable at 90d age, but HSLAC still has a high AS growth. It is found that adjusting the volume rate of lightweight aggregate, mixing with a proper dosage of fly ash and raising the water saturation degree of lightweight aggregate can markedly reduce the AS rate of HSLAC.

  8. Surgical treatment of multifocal giant cell tumor of carpal bones with preservation of wrist function: case report.

    Science.gov (United States)

    Tarng, Yih-Wen; Yang, Shan-Wei; Hsu, Chien-Jen

    2009-02-01

    We report a rare case of multifocal giant cell tumor of bone involving the trapezium, trapezoid, capitate, and scaphoid with soft tissue extension. Following intralesional resection, an autogenous corticocancellous iliac crest bone graft was used to fill the resultant defect and preserve carpal height and radiocarpal motion. Successful union with no recurrence was noted at 1-year follow-up.

  9. Adjuvant auricular electroacupuncture and autogenic training in rheumatoid arthritis: a randomized controlled trial

    DEFF Research Database (Denmark)

    Bernateck, M.; Becker, M.; Schwacke, C.

    2008-01-01

    BACKGROUND: In contrast to psychological interventions the usefulness of acupuncture as an adjuvant therapy in rheumatoid arthritis (RA) has not yet been demonstrated. OBJECTIVE: The efficacy of auricular electroacupuncture (EA) was directly compared with autogenic training (AT). METHODS: Patients...

  10. Peculiarities of application the method of autogenic training in the correction of eating behavior

    OpenAIRE

    Shebanova, Vitaliya

    2014-01-01

    The article presented peculiarities of applying the method of autogenic training in the correction of eating disorders. Described stages of correction work with desadaptive eating behavior. Author makes accent on the rules self-assembly formula intentions.

  11. ANEURYSMAL BONE CYST OF THE CLAVICLE IN CHILDREN (CLINICAL CASES AND TREATMENT

    Directory of Open Access Journals (Sweden)

    Тимур Фаизович Зубаиров

    2014-09-01

    Full Text Available The purpose. To examine the results of the treatment of children with aneurysmal cyst of the clavicle. Material and methods. The results of examination and treatment of patients aged 16 and 17 years with a diagnosis of aneurysmal cyst of the clavicle. All patients underwent surgical treatment with the ABC stage delimitation. We used a surgical technique, which consists in open removement of the abnormal tissue with replacement of the bone defect with bone-plastic material or autogenous bone from the iliac crest. Conclusions. The method of treatment of aneurysmal bone cyst of the clavicle must be individualized depending on the location, aggressiveness and extent of the lesion. The use bone-plastic material or autogenous bone from the iliac crest restore the structural integrity of a compromised clavicle gives good results in the observation period of up to 2 years.

  12. Allergies, asthma, and dust

    Science.gov (United States)

    Reactive airway disease - dust; Bronchial asthma - dust; Triggers - dust ... Things that make allergies or asthma worse are called triggers. Dust is a common trigger. When your asthma or allergies become worse due to dust, you are ...

  13. Changes of Ca2+ activated potassium channels and cellular proliferation in autogenous vein grafts

    Institute of Scientific and Technical Information of China (English)

    钱济先; 宋胜云; 马保安; 范清宇

    2003-01-01

    Objective: To investigate changes of Ca2+ activated potassium channels (KCa) in autogenous vein grafts. Methods: Contraction of venous ring was measured by means of perfusion in vitro. The intimal rabbits proliferation of vascular and proliferation of cultured smooth muscle cells(vascular smooth muscle cells, VSMCs)were observed by the means of computerised image analysis and MTT method respectively. Furthermore, whole cell mode of patch clamp was used to record KCa of VSMCs isolated from autogenous vein grafts. Results: One week after transplantation there were no significant differences of contraction and intimal relative thickness between autogenous vein grafts and control. Contraction and intimal relative thickness of autogenous vein graft were significantly increased 2 weeks after transplantation (P<0.05, n=8 vs control), and they was more enhanced 4 weeks after vein transplantation (P<0.01, n=8 vs control).TEA(blocker of Ca2+ activated potassium channels)increased MTT A490 nm value of VSMCs from femoral vein in a dose dependent manner(P<0.05, n=8). KCa current density was significantly attenuated in VSMCs from autogenous vein grafts (1-4) week after transplantation(P<0.05, n=5).Conclusion: KCa is inhibited in autogenous vein graft, which account for vasospasm and intimal proliferation.

  14. Is bone transplantation the gold standard for repair of alveolar bone defects?

    Directory of Open Access Journals (Sweden)

    Cassio Eduardo Raposo-Amaral

    2014-01-01

    Full Text Available New strategies to fulfill craniofacial bone defects have gained attention in recent years due to the morbidity of autologous bone graft harvesting. We aimed to evaluate the in vivo efficacy of bone tissue engineering strategy using mesenchymal stem cells associated with two matrices (bovine bone mineral and α-tricalcium phosphate, compared to an autologous bone transfer. A total of 28 adult, male, non-immunosuppressed Wistar rats underwent a critical-sized osseous defect of 5 mm diameter in the alveolar region. Animals were divided into five groups. Group 1 (n = 7 defects were repaired with autogenous bone grafts; Group 2 (n = 5 defects were repaired with bovine bone mineral free of cells; Group 3 (n = 5 defects were repaired with bovine bone mineral loaded with mesenchymal stem cells; Group 4 (n = 5 defects were repaired with α-tricalcium phosphate free of cells; and Group 5 (n = 6 defects were repaired with α-tricalcium phosphate loaded with mesenchymal stem cells. Groups 2–5 were compared to Group 1, the reference group. Healing response was evaluated by histomorphometry and computerized tomography. Histomorphometrically, Group 1 showed 60.27% ± 16.13% of bone in the defect. Groups 2 and 3 showed 23.02% ± 8.6% (p = 0.01 and 38.35% ± 19.59% (p = 0.06 of bone in the defect, respectively. Groups 4 and 5 showed 51.48% ± 11.7% (p = 0.30 and 61.80% ± 2.14% (p = 0.88 of bone in the defect, respectively. Animals whose bone defects were repaired with α-tricalcium phosphate and mesenchymal stem cells presented the highest bone volume filling the defects; both were not statistically different from autogenous bone.

  15. Is bone transplantation the gold standard for repair of alveolar bone defects?

    Science.gov (United States)

    Raposo-Amaral, Cassio Eduardo; Bueno, Daniela Franco; Almeida, Ana Beatriz; Jorgetti, Vanda; Costa, Cristiane Cabral; Gouveia, Cecília Helena; Vulcano, Luiz Carlos; Fanganiello, Roberto D; Passos-Bueno, Maria Rita

    2014-01-01

    New strategies to fulfill craniofacial bone defects have gained attention in recent years due to the morbidity of autologous bone graft harvesting. We aimed to evaluate the in vivo efficacy of bone tissue engineering strategy using mesenchymal stem cells associated with two matrices (bovine bone mineral and α-tricalcium phosphate), compared to an autologous bone transfer. A total of 28 adult, male, non-immunosuppressed Wistar rats underwent a critical-sized osseous defect of 5 mm diameter in the alveolar region. Animals were divided into five groups. Group 1 (n = 7) defects were repaired with autogenous bone grafts; Group 2 (n = 5) defects were repaired with bovine bone mineral free of cells; Group 3 (n = 5) defects were repaired with bovine bone mineral loaded with mesenchymal stem cells; Group 4 (n = 5) defects were repaired with α-tricalcium phosphate free of cells; and Group 5 (n = 6) defects were repaired with α-tricalcium phosphate loaded with mesenchymal stem cells. Groups 2–5 were compared to Group 1, the reference group. Healing response was evaluated by histomorphometry and computerized tomography. Histomorphometrically, Group 1 showed 60.27% ± 16.13% of bone in the defect. Groups 2 and 3 showed 23.02% ± 8.6% (p = 0.01) and 38.35% ± 19.59% (p = 0.06) of bone in the defect, respectively. Groups 4 and 5 showed 51.48% ± 11.7% (p = 0.30) and 61.80% ± 2.14% (p = 0.88) of bone in the defect, respectively. Animals whose bone defects were repaired with α-tricalcium phosphate and mesenchymal stem cells presented the highest bone volume filling the defects; both were not statistically different from autogenous bone. PMID:24551445

  16. Autogenous tendon double bone-tunnel reconstruction technique to repair the posterolateral rotating instability of the elbow%自体肌腱双骨隧道重建技术修复肘关节后外侧旋转不稳定

    Institute of Scientific and Technical Information of China (English)

    刘大海; 李开南; 母建松; 兰海

    2016-01-01

    Background The concept of posterolateral rotatory instability (PLRI)of the elbow was proposed in 1991 by O′Driscoll for the first time.The pathogenic mechanism of PLRI is injury to the radial collateral ligament complex at the elbow,among which the lateral ulnar collateral ligament (LUCL) plays a major role. However, because most physicians know little about the elbow dysfunction caused by such ligament inj ury,missed or delayed diagnosis often prevents timely and effective treatment,leading to seriously impact on the quality of life of patients.Surgical treatment is often very effective,but surgical approaches vary a lot.Rhyou et al established a horizontal bone tunnel cross the humerus for passing through the tendon,but this approach doesn′t allow attachment of the upper end of this ligament on the lateral condyle of the humerus. Sanchez-Sotelo et al. established bone tunnel on ulna and humerus perpendicular to the ligament,and passed longer tendon through the tunnel at an"8"shape,which was immobilized by suture knot.This procedure requires that the tendon have to be a long and thin one while problems such as tendon breakage and suture slippage often happen.The way Dehlinger et al.established the bone tunnel was similar to the present study,i.e.,after passing the bone tunnel;the tendon was only fixed to the bone marrow with suture. This method also has the disadvantage of poor stability and delayed functional exercise.This study used autologous tendon and established humerus and ulna double bone tunnel for ligament reconstruction in 16 patients and the treatment effect is reported below.Methods From January 2008 to December 2013,orthopedics division of our hospital admitted and diagnosed 16 cases of elbow LUCL tear with PLRI patients,of which 11 males and 5 females,aged 19-43 years old,average age of 28.8 years old,7 cases of fresh injuries and 9 cases of old injuries,4 cases of simple ulnar coronoid process fracture,3 cases of elbow dislocation,5 cases of

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

    Science.gov (United States)

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

    2015-01-01

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

  18. The Palatal Bone Block Graft for Onlay Grafting Combined with Maxillary Implant Placement: A Case Series.

    Science.gov (United States)

    Gluckman, Howard; Du Toit, Jonathan; Salama, Maurice

    2016-01-01

    The aim of this study was to introduce an intraoral bone block harvesting technique--the palatal bone block graft (PBBG)--as an alternative harvest site for autogenous bone blocks. The PBBG technique was used to onlay graft esthetic zone defects simultaneous to implant placement in five patients. Measurable objectives were used to evaluate outcomes, and treatment was reassessed at up to 6 years. Defects of the maxilla were successfully grafted with PBBG in all five cases, and tissues remained stable at 1- and 6-year follow-ups. Harvesting an autogenous bone block from the palate is an advantageous, predictable, and reproducible method for augmenting buccofacial defects at implant placement, and may be considered as an alternative to conventional intraoral bone block donor sites when treating the maxilla.

  19. Autogenic training: a meta-analysis of clinical outcome studies.

    Science.gov (United States)

    Stetter, Friedhelm; Kupper, Sirko

    2002-03-01

    Autogenic training (AT) is a self-relaxation procedure by which a psychophysiological determined relaxation response is elicited. A meta-analysis was performed to evaluate the clinical effectiveness of AT. Seventy-three controlled outcome studies were found (published 1952-99). Sixty studies (35 randomized controlled trials [RCT]) qualified for inclusion in the meta-analysis. Medium-to-large effect sizes (ES) occurred for pre-post comparisons of disease-specific AT-effects, with the RCTs showing larger ES. When AT was compared to real control conditions, medium ES were found. Comparisons of AT versus other psychological treatment mostly resulted in no effects or small negative ES. This pattern of results was stable at follow-up. Unspecific AT-effects (i.e., effects on mood, cognitive performance, quality of life, and physiological variables) tended to be even larger than main effects. Separate meta-analyses for different disorders revealed a significant reduction of the heterogeneity of ES. Positive effects (medium range) of AT and of AT versus control in the meta-analysis of at least 3 studies were found for tension headache/migraine, mild-to-moderate essential hypertension, coronary heart disease, asthma bronchiale, somatoform pain disorder (unspecified type), Raynaud's disease, anxiety disorders, mild-to-moderate depression/dysthymia, and functional sleep disorders.

  20. Reorganization of the Brain and Heart Rhythm During Autogenic Meditation

    Directory of Open Access Journals (Sweden)

    Dae-Keun eKim

    2014-01-01

    Full Text Available The underlying changes in heart coherence that are associated with reported EEG changes in response to meditation have been explored. We measured EEG and heart rate variability (HRV before and during autogenic meditation. Fourteen subjects participated in the study. Heart coherence scores were significantly increased during meditation compared to the baseline. We found near significant decrease in high beta absolute power, increase in alpha relative power and significant increases in lower(alpha and higher(above beta band coherence during 3 minute epochs of heart coherent meditation compared to 3 minute epochs of heart noncoherence at baseline. The coherence and relative power increase in alpha band and absolute power decrease in high beta band could reflect relaxation state during the heart coherent meditation. The coherence increase in the higher(above beta band could reflect cortico-cortical local integration and thereby affect cognitive reorganization, simultaneously with relaxation. Further research is still needed for a confirmation of heart coherence as a simple window for the meditative state.

  1. Pilot study of autogenous tooth dentin graft to repair bone defect%正畸牙移动模型的建立及昼夜节律基因per1在其牙周组织中的表达

    Institute of Scientific and Technical Information of China (English)

    李维康; 秦旭; 管玮; 邓捷; 刘梦; 白宇明; 毛靖

    2015-01-01

    Objective:To establish animal model for orthodontic tooth movement and investigate the expression of per1 in periodontal tissues. Method:After one week adapting period under 12 h light and 12 h dark,8-week-old male Sprague Dawley (SD) rats were installed a piece of orthodontic appliance between maxillary central incisors and maxillary right first molar. The distance of movement was measured by micro-CT during next two weeks. Then,some maxillaries were used to histological analysis and Real-time quantitative PCR assays were performed to quantify expression of the core circa-dian gene per1 in the other periodontal tissues around movement teeth. Result:The average distance of first molar was 0.45 mm after two weeks. Alveolar bone was resorptive on the pressure side and new bone was of formation on the tension side. The expression of per1 was accordance with cosine curve during 24 h. Conclusion:Per1 was found and maintained the cir-cadian rhythm in orthodontic periodontal tissue.%目的:建立正畸牙移动模型并研究正畸加力组织中昼夜节律基因per1表达的规律性。方法:选取8周龄雄性SD大鼠,按照照明和黑暗时间相等的条件下饲养1周后,每只鼠在上颌前牙与右侧上颌第一磨牙间安装正畸加力装置。矫正2周,micro-CT测量牙齿水平移动距离。2周后将9组SD鼠分别在24h内的9个等距时间节点处死,处死后取正畸加力组织分别行组织学分析和昼夜节律基因per1的定量检测。结果:矫正2周后,牙齿的平均移动距离0.45 mm。形态学分析显示第一磨牙近中牙槽骨吸收,远中有新形成骨。实时荧光定量PCR结果提示昼夜节律基因per1在24 h内的变化呈余弦函数曲线。结论:使用正畸加力装置矫正的牙周组织中存在昼夜节律基因per1的表达并有昼夜节律性。

  2. The use of absorbable membranes for Guided Bone Regeneration in horizontal localized bone defects.

    Directory of Open Access Journals (Sweden)

    Adamantia VLACHAKI

    2016-08-01

    Full Text Available SUMMARY: One of the most widely used techniques for the reconstruction of horizontal alveolar defects is Guided Bone Regeneration (GBR. Aim of this literature review is to present and evaluate the clinical techniques for horizontal GBR in localized bone defects with the use of bone grafts and barrier absorbable membranes. In order to accomplish this literature review, a survey in website Pubmed was carried out, with key words: GBR in horizontal defects, GBR in localized defects, bone substitutes, absorbable membranes. Experimental animal studies, studies which described the autogenous block techniques and studies which described GBR with nonabsorbable membranes were excluded from this literature review. GBR was found to be a well document and predictable technique for horizontal localized bone defects, in order to place dental implants. Also the use of xenogenous bone graft in combination with absorbable membrane presents a lot of encouraging results, with high success and survival implant rate.

  3. A new biological approach to guided bone and tissue regeneration.

    Science.gov (United States)

    Montanari, Marco; Callea, Michele; Yavuz, Izzet; Maglione, Michele

    2013-04-09

    The purpose of this study was to determine the potential of platelet-rich fibrin (PRF) membranes used for guided bone and tissue regeneration. A patient with insufficient alveolar ridge width in aesthetic zone was enrolled. The patient's blood was centrifuged to obtain PRF membranes. Autogenous bone graft was mixed with bovine hydroxyapatite, PRF particles and applied to fill the defect. Five PRF membranes were placed over the bone mix. After 4 months a cone-beam CT was performed to evaluate bone regeneration. The use of PRF as cover membrane permitted a rapid epithelisation and represented an effective barrier versus epithelial cell penetration. After 4 months the site appeared precociously healed and the bone volume increased. This new approach represents a predictable method of augmenting deficient alveolar ridges. Guided bone regeneration with PRF showed limitation compared with guided bone regeneration using collagen membrane in terms of bone gain. The association of collagen membrane and PRF could be a good association.

  4. Brain structural alterations in obsessive-compulsive disorder patients with autogenous and reactive obsessions.

    Directory of Open Access Journals (Sweden)

    Marta Subirà

    Full Text Available Obsessive-compulsive disorder (OCD is a clinically heterogeneous condition. Although structural brain alterations have been consistently reported in OCD, their interaction with particular clinical subtypes deserves further examination. Among other approaches, a two-group classification in patients with autogenous and reactive obsessions has been proposed. The purpose of the present study was to assess, by means of a voxel-based morphometry analysis, the putative brain structural correlates of this classification scheme in OCD patients. Ninety-five OCD patients and 95 healthy controls were recruited. Patients were divided into autogenous (n = 30 and reactive (n = 65 sub-groups. A structural magnetic resonance image was acquired for each participant and pre-processed with SPM8 software to obtain a volume-modulated gray matter map. Whole-brain and voxel-wise comparisons between the study groups were then performed. In comparison to the autogenous group, reactive patients showed larger gray matter volumes in the right Rolandic operculum. When compared to healthy controls, reactive patients showed larger volumes in the putamen (bilaterally, while autogenous patients showed a smaller left anterior temporal lobe. Also in comparison to healthy controls, the right middle temporal gyrus was smaller in both patient subgroups. Our results suggest that autogenous and reactive obsessions depend on partially dissimilar neural substrates. Our findings provide some neurobiological support for this classification scheme and contribute to unraveling the neurobiological basis of clinical heterogeneity in OCD.

  5. Numerical model predictions of autogenic fluvial terraces and comparison to climate change expectations

    Science.gov (United States)

    Limaye, Ajay B. S.; Lamb, Michael P.

    2016-03-01

    Terraces eroded into sediment (alluvial) and bedrock (strath) preserve an important history of river activity. River terraces are thought to form when a river switches from a period of slow vertical incision and valley widening to fast vertical incision and terrace abandonment. Consequently, terraces are often interpreted to reflect changing external drivers including tectonics, sea level, and climate. In contrast, the intrinsic unsteadiness of lateral migration in rivers may generate terraces even under constant rates of vertical incision without external forcing. To explore this mechanism, we simulate landscape evolution by a vertically incising, meandering river and isolate the age and geometry of autogenic river terraces. Modeled autogenic terraces form for a wide range of lateral and vertical incision rates and are often paired and longitudinally extensive for intermediate ratios of vertical-to-lateral erosion rate. Autogenic terraces have a characteristic reoccurrence time that scales with the time for relief generation. There is a preservation bias against older terraces due to reworking of previously visited parts of the valley. Evolving, spatial differences in bank strength between bedrock and sediment reduce terrace formation frequency and length, favor pairing, and can explain sublinear terrace margins at valley boundaries. Age differences and geometries for modeled autogenic terraces are consistent, in cases, with natural terraces and overlap with metrics commonly attributed to terrace formation due to climate change. We suggest a new phase space of terrace properties that may allow differentiation of autogenic terraces from terraces formed by external drivers.

  6. Bone grafting of the floor of the maxillary sinus for the placement of endosseous implants

    NARCIS (Netherlands)

    Raghoebar, GM; Vissink, A; Reintsema, H; Batenburg, RHK

    1997-01-01

    This study describes and evaluates a technique to augment the floor of the maxillary sinus and to widen the alveolar crest of the atrophic posterior maxilla with autogenous bone. The subjects were 43 patients whose maxillary alveolar crest was not high enough to permit reliable placement of endosseo

  7. The influence of superabsorbent polymers on the autogenous shrinkage properties of cement pastes with supplementary cementitious materials

    DEFF Research Database (Denmark)

    Snoeck, D.; Jensen, Ole Mejlhede; De Belie, N.

    2015-01-01

    Fly ash and blast-furnace slag containing binders are frequently used in the construction industry and it is important to know the extent of autogenous shrinkage and its (ideal) mitigation by superabsorbent polymers in these systems as a function of their age. In this paper, the autogenous shrink...

  8. Experimental Research on the Autogenous Shrinkage of MK High Performance Concrete

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Calcine and mill kaolin were used under agreeable technological conditions to generate matakaolin (MK). The autogenous shrinkage performance of high performance concrete added with MK was researched. It is shown that MK has an effective inhibitory action to early autogenous shrinkage of cement concrete, and the inhibitory action increases with the increase of MK. The autogenous shrinkage values from 24 hours after placement to 56 days are all higher than those of the contrasted concrete, among which, the value of the concrete with 5% MK is the highest. But the total shrinkage values in 56 days are all less than those of the contrasted test pieces. The total contraction after 24 h of placement decreases as the increase of MK, moreover,it is greatly less than that of the contrasted ones.

  9. Cloning and expression of autogenes encoding RNA polymerases of T7-like bacteriophages

    Energy Technology Data Exchange (ETDEWEB)

    Studier, F. William (Stony Brook, NY); Dubendorff, John W. (Sound Beach, NY)

    1998-01-01

    This invention relates to the cloning and expression of autogenes encoding RNA polymerases of T7 and T7-like bacteriophages, in which the RNA polymerase gene is transcribed from a promoter which is recognized by the encoded RNA polymerase. Cloning of T7 autogenes was achieved by reducing the activity of the RNA polymerase sufficiently to permit host cell growth. T7 RNA polymerase activity was controlled by combining two independent methods: lac-repression of the recombinant lac operator-T7 promoter in the autogene and inhibition of the polymerase by T7 lysozyme. Expression systems for producing the RNA polymerases of T7 and other T7-like bacteriophages, and expression systems for producing selected gene products are described, as well as other related materials and methods.

  10. Cloning and expression of autogenes encoding RNA poly,erases of T7-like bacteriophages

    Energy Technology Data Exchange (ETDEWEB)

    Studier, F. William (Stony Brook, NY); Dubendorff, John W. (Sound Beach, NY)

    1998-01-01

    This invention relates to the cloning and expression of autogenes encoding RNA polymerases of T7 and T7-like bacteriophages, in which the RNA polymerase gene is transcribed from a promoter which is recognized by the encoded RNA polymerase. Cloning of T7 autogenes was achieved by reducing the activity of the RNA polymerase sufficiently to permit host cell growth. T7 RNA polymerase activity was controlled by combining two independent methods: lac-repression of the recombinant lac operator-T7 promoter in the autogene and inhibition of the polymerase by T7 lysozyme. Expression systems for producing the RNA polymerases of T7 and other T7-like bacteriophages, and expression systems for producing selected gene products are described, as well as other related materials and methods.

  11. Cloning and expression of autogenes encoding RNA polymerases of T7-like bacteriophages

    Energy Technology Data Exchange (ETDEWEB)

    Studier, F.W.; Dubendorff, J.W.

    1998-10-20

    This invention relates to the cloning and expression of autogenes encoding RNA polymerases of T7 and T7-like bacteriophages, in which the RNA polymerase gene is transcribed from a promoter which is recognized by the encoded RNA polymerase. Cloning of T7 autogenes was achieved by reducing the activity of the RNA polymerase sufficiently to permit host cell growth. T7 RNA polymerase activity was controlled by combining two independent methods: lac-repression of the recombinant lac operator-T7 promoter in the autogene and inhibition of the polymerase by T7 lysozyme. Expression systems for producing the RNA polymerases of T7 and other T7-like bacteriophages, and expression systems for producing selected gene products are described, as well as other related materials and methods. 12 figs.

  12. Cloning and expression of autogenes encoding RNA polymerases of T7-like bacteriophages

    Energy Technology Data Exchange (ETDEWEB)

    Studier, F.W.; Dubendorff, J.W.

    1998-11-03

    This invention relates to the cloning and expression of autogenes encoding RNA polymerases of T7 and T7-like bacteriophages, in which the RNA polymerase gene is transcribed from a promoter which is recognized by the encoded RNA polymerase. Cloning of T7 autogenes was achieved by reducing the activity of the RNA polymerase sufficiently to permit host cell growth. T7 RNA polymerase activity was controlled by combining two independent methods: lac-repression of the recombinant lac operator-T7 promoter in the autogene and inhibition of the polymerase by T7 lysozyme. Expression systems for producing the RNA polymerases of T7 and other T7-like bacteriophages, and expression systems for producing selected gene products are described, as well as other related materials and methods. 12 figs.

  13. Evaluation of Aquacel Ag for Autogenous Skin Donor Sites.

    Science.gov (United States)

    Haith, Linwood R; Stair-Buchmann, Megan E; Ackerman, Bruce H; Herder, Diane; Reigart, Cynthia L; Stoering, Marla; Guilday, Robert E; Patton, Mary Lou; Ross, Kerry M

    2015-01-01

    An ongoing objective of burn research is to evaluate wound dressings and develop new treatments to expedite wound healing. This was a single-center, prospective, randomized, controlled study to evaluate the effectiveness of Aquacel Ag as a dressing for autogenous skin donor sites compared with Xeroform. We hypothesized that donor sites treated with Aquacel Ag would heal faster. Patients were considered for enrollment if they required skin grafting with two donor sites >100 cm at least 2 inches apart. Dressings were observed daily starting on post-op day #2 until discharge and then weekly in the outpatient burn clinic. Assessments evaluated pain, infection, and reapplication. Photographs were taken on post-op day #2, upon "90% re-epithelialization," and at post-op day #30-45. Scar assessments and blinded photographic reviews were completed to assess cosmetic healing. Twenty-nine patients completed the study. Re-epithelialization occurred faster with Xeroform (15.2 days vs. 17.6 days). Daily pain scores were higher with Xeroform (6.72 vs. 5.68) and Aquacel Ag needed to be replaced more often (1.72 times vs. 0.10 times). Three patients developed donor site infections with Aquacel Ag. Scar scores between the donor sites were not statistically significant. The blinded photo review concluded that Xeroform had a better cosmetic outcome (24 vs. 10%). Although patients complained of more pain with Xeroform, it demonstrated shorter healing times and better cosmetic outcomes. Aquacel Ag needed to be replaced more often and represented the only three donor site infections.

  14. Autogenous tooth transplants for the pediatric dental patient: report of three cases.

    Science.gov (United States)

    Kennedy, David

    2013-01-01

    There are select instances where autogenous tooth transplantation should be considered as part of the overall management of the developing occlusion in the child patient. These circumstances occur when there are missing mandibular premolars in Class II malocclusions with good faces, unevenly distributed agenesis, missing or lost incisors, and ectopic teeth. The purposes of this paper were to educate pediatric dentists about the autogenous tooth transplantation technique, its success, its potential advantages and disadvantages and to report on three cases treated with autogenesis tooth transplantation.

  15. Autogenous vein graft thrombosis following exposure to calcium-free solutions (calcium paradox).

    Science.gov (United States)

    Nozick, J H; Farnsworth, P; Montefusco, C M; Parsonnet, V; Ruigrok, T J; Zimmerman, A N

    1981-01-01

    The morphological and functional effects of calcium-free and calcium-containing solutions on canine jugular vein intima were examined under conditions which closely resemble those techniques currently employed in peripheral vascular and aortocoronary bypass surgery. Veins that had been exposed only to calcium-containing solutions remained patent for the duration of the experimental period. Vein perfusion with a calcium-free solution, however, resulted in disruption of the jugular vein intima once calcium ions were reintroduced. Autogenous as a femoral arterial graft became thrombosed within 60 minutes. It is therefore suggested that vein grafts of autogenous origin be irrigated with calcium-containing solutions to prevent intimal damage and thrombosis.

  16. Bone tumor

    Science.gov (United States)

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

  17. Revision Rotator Cuff Reconstruction for Large Tears With Retraction: A Novel Technique Using Autogenous Tendon and Autologous Marrow.

    Science.gov (United States)

    Skoff, Hillel D

    2015-07-01

    Revision rotator cuff reconstruction for large tears with retraction results in a high rate of recurrent cuff tearing. To try to obtain more consistent results, I conducted a study of a technique that addresses the potential factors involved. Ten patients (7 men, 3 women) were enrolled. Mean age was 58 years. Mean follow-up was 24 months. Mean time between primary and revision cuff surgery was 36 months. The cardinal inclusion criterion was a symptomatic, full-thickness rotator cuff tear with at least 3 cm of retraction in a shoulder that previously underwent rotator cuff repair. Ultrasound was used for postoperative radiographic assessment of cuff integrity. Validated Constant, American Shoulder and Elbow Surgeons (ASES), and University of California Los Angeles (UCLA) shoulder scoring systems were used. Surgical technique included mini-open incision, adequate débridement and mobilization of remaining cuff, reconstitution of cuff defect with autogenous biceps tendon incubated in concentrated autologous bone marrow, and sewing under zero tissue tension. Constant, ASES, and UCLA scores improved significantly (standard error at .001). Ultrasound revealed 0% incidence of full-thickness rotator cuff retearing. In patients with large recurrent retracted rotator cuff tears the technique presented in the current study consistently yields satisfactory clinical results and promotes rotator cuff tissue healing without full-thickness retearing.

  18. Current and emerging basic science concepts in bone biology: implications in craniofacial surgery.

    Science.gov (United States)

    Oppenheimer, Adam J; Mesa, John; Buchman, Steven R

    2012-01-01

    Ongoing research in bone biology has brought cutting-edge technologies into everyday use in craniofacial surgery. Nonetheless, when osseous defects of the craniomaxillofacial skeleton are encountered, autogenous bone grafting remains the criterion standard for reconstruction. Accordingly, the core principles of bone graft physiology continue to be of paramount importance. Bone grafts, however, are not a panacea; donor site morbidity and operative risk are among the limitations of autologous bone graft harvest. Bone graft survival is impaired when irradiation, contamination, and impaired vascularity are encountered. Although the dura can induce calvarial ossification in children younger than 2 years, the repair of critical-size defects in the pediatric population may be hindered by inadequate bone graft donor volume. The novel and emerging field of bone tissue engineering holds great promise as a limitless source of autogenous bone. Three core constituents of bone tissue engineering have been established: scaffolds, signals, and cells. Blood supply is the sine qua non of these components, which are used both individually and concertedly in regenerative craniofacial surgery. The discerning craniofacial surgeon must determine the proper use for these bone graft alternatives, while understanding their concomitant risks. This article presents a review of contemporary and emerging concepts in bone biology and their implications in craniofacial surgery. Current practices, areas of controversy, and near-term future applications are emphasized.

  19. Evaluation of Autogenous Engineered Septal Cartilage Grafts in Rabbits: A Minimally Invasive Preclinical Model

    Directory of Open Access Journals (Sweden)

    Anton Kushnaryov

    2014-01-01

    Full Text Available Objectives. (1 Evaluate safety of autogenous engineered septal neocartilage grafts and (2 compare properties of implanted grafts versus controls. Study Design. Prospective, basic science. Setting. Research laboratory. Methods. Constructs were fabricated from septal cartilage and then cultured in vitro or implanted on the nasal dorsum as autogenous grafts for 30 or 60 days. Rabbits were monitored for local and systemic complications. Histological, biochemical, and biomechanical properties of constructs were evaluated. Results. No serious complications were observed. Implanted constructs contained more DNA (P<0.01 and less sGAG perDNA (P<0.05 when compared with in vitro controls. Confined compressive aggregate moduli were also higher in implanted constructs (P<0.05 and increased with longer in vivo incubation time (P<0.01. Implanted constructs displayed resorption rates of 20–45 percent. Calcium deposition in implanted constructs was observe. Conclusion. Autogenous engineered septal cartilage grafts were well tolerated. As seen in experiments with athymic mice, implanted constructs accumulated more DNA and less sGAG when compared with in vitro controls. Confined compressive aggregate moduli were higher in implanted constructs. Implanted constructs displayed resorption rates similar to previously published studies using autogenous implants of native cartilage.

  20. Neural progenitor cells from human induced pluripotent stem cells generated less autogenous immune response.

    Science.gov (United States)

    Huang, Ke; Liu, PengFei; Li, Xiang; Chen, ShuBin; Wang, LiHui; Qin, Li; Su, ZhengHui; Huang, WenHao; Liu, Juli; Jia, Bei; Liu, Jie; Cai, JingLei; Pei, DuanQing; Pan, GuangJin

    2014-02-01

    The breakthrough development of induced pluripotent stem cells (iPSCs) raises the prospect of patient-specific treatment for many diseases through the replacement of affected cells. However, whether iPSC-derived functional cell lineages generate a deleterious immune response upon auto-transplantation remains unclear. In this study, we differentiated five human iPSC lines from skin fibroblasts and urine cells into neural progenitor cells (NPCs) and analyzed their immunogenicity. Through co-culture with autogenous peripheral blood mononuclear cells (PBMCs), we showed that both somatic cells and iPSC-derived NPCs do not stimulate significant autogenous PBMC proliferation. However, a significant immune reaction was detected when these cells were co-cultured with allogenous PBMCs. Furthermore, no significant expression of perforin or granzyme B was detected following stimulation of autogenous immune effector cells (CD3(+)CD8(-) T cells, CD3(+)CD8(+) T cells or CD3(-)CD56(+) NK cells) by NPCs in both PBMC and T cell co-culture systems. These results suggest that human iPSC-derived NPCs may not initiate an immune response in autogenous transplants, and thus set a base for further preclinical evaluation of human iPSCs.

  1. Starch hydrolysis in autogenerative high pressure digestion: Gelatinisation and saccharification as rate limiting steps

    NARCIS (Netherlands)

    Lindeboom, R.E.F.; Ding, L.; Weijma, J.; Plugge, C.M.; Lier, van J.B.

    2014-01-01

    Autogenerative high pressure digestion (AHPD) provides an integrated biogas upgrading technology, capable of producing biogas with a CH4 content exceeding 95% at pressures up to 90 bar. Hydrolysis is generally regarded as the rate-limiting step in the anaerobic digestion of complex organic matter, g

  2. Autogenous shrinkage of Ducorit S5R ASTM C 1698-09 test method

    DEFF Research Database (Denmark)

    Damkilde, Lars

    The report deals with experimental measurement of autogenous shrinkage of Ducorit S5R according to the test method ASTM C 1698-09. This test method measures the bulk strain of a sealed cementitious specimen, at constant temperature and not subjected to external forces, from the time of final...

  3. Acromioclavicular Reconstruction using Autogenous Semitendinosus Tendon Graft and the Importance of Postoperative Rehabilitation: A Case Report

    Directory of Open Access Journals (Sweden)

    Jade PY Ho

    2013-11-01

    Full Text Available We present a case of chronic acromioclavicular joint dislocation (Rockwood type 5 in which the choice of acromioclavicular reconstruction using autogenous semitendinosus tendon graft was made due to its superiority in anatomical reconstruction of the coracoclavicular ligaments, and the impact of postoperative rehabilitation on the recovery of this patient. We also discuss the rationale behind this.

  4. The effect of platelet-rich plasma on early and late bone healing: an experimental study in goats.

    NARCIS (Netherlands)

    Mooren, R.E.C.M.; Merkx, M.A.W.; Bronkhorst, E.M.; Jansen, J.A.; Stoelinga, P.J.W.

    2007-01-01

    Four round critical-size defects were made in the foreheads of 20 goats. The defects were filled with autogenous particulate cancellous bone, in which 1 ml of platelet-rich plasma (PRP) was added in two of the four defects of each goat. The goats were divided into four subgroups of five goats each,

  5. Role of ferrite and phosphorus plus sulphur in the crack sensitivity of autogenously welded type 309 stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, Jr., F. J.

    1976-07-01

    A study on autogenous welding of Type 309 thin stainless steel sheet was made after experiencing cracking difficulties on several commercial heats. A relationship exists between the sum of the phosphorus plus sulfur, the ferrite control of the weld metal, and the crack sensitivity of autogenously made welds. A new simple weld test for thin-gage sheet is utilized for studying the susceptibility to cracking. A chemistry modification is suggested to alleviate possible weld cracking when autogenously welding this grade. The principles of crack sensitivity prediction could apply to other austenitic stainless steel types where chemistry limits are such that ferrite is possible.

  6. 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.

  7. Comprehensive Review of Adipose Stem Cells and Their Implication in Distraction Osteogenesis and Bone Regeneration

    Directory of Open Access Journals (Sweden)

    Mina W. Morcos

    2015-01-01

    Full Text Available Bone is one of the most dynamic tissues in the human body that can heal following injury without leaving a scar. However, in instances of extensive bone loss, this intrinsic capacity of bone to heal may not be sufficient and external intervention becomes necessary. Several techniques are available to address this problem, including autogenous bone grafts and allografts. However, all these techniques have their own limitations. An alternative method is the technique of distraction osteogenesis, where gradual and controlled distraction of two bony segments after osteotomy leads to induction of new bone formation. Although distraction osteogenesis usually gives satisfactory results, its major limitation is the prolonged duration of time required before the external fixator is removed, which may lead to numerous complications. Numerous methods to accelerate bone formation in the context of distraction osteogenesis have been reported. A viable alternative to autogenous bone grafts for a source of osteogenic cells is mesenchymal stem cells from bone marrow. However, there are certain problems with bone marrow aspirate. Hence, scientists have investigated other sources for mesenchymal stem cells, specifically adipose tissue, which has been shown to be an excellent source of mesenchymal stem cells. In this paper, the potential use of adipose stem cells to stimulate bone formation is discussed.

  8. The Formation of Carbon Nanostructures via Catalytic Pyrolysis of Naphthalene under Its Autogenic Pressure

    Directory of Open Access Journals (Sweden)

    Chao-Gang Wang

    2015-01-01

    Full Text Available The formation of carbon nanotubes (CNTs, spherical carbon nanocapsules (CNCs, and carbon spheres (CSs is accomplished by using the method of reactions under autogenic pressure at elevated temperatures (RAPET. A powder mixture of naphthalene and nickel acetate tetrahydrate is dissociated under its autogenic pressure. The resultant CNTs and CNCs exhibit good graphitic quality, and the diameters range from 50~200 nm. Smooth and monodisperse CSs with the diameter ranging from 5~10 μm can be obtained by pyrolysis of pure naphthalene. Our results show that the reaction temperature and catalyst proportion play a key role in the formation of carbon nanostructures with RAPET method.

  9. Combined use of autogenic therapy and biofeedback in training effective control of heart rate by humans

    Science.gov (United States)

    Cowings, P. S.

    1977-01-01

    Experiments were performed on 24 men and women (aged 20-27 yr) in three equal groups who were taught to control their own heart rates by autogenic training and biofeedback under dark and sound-isolated conditions. Group I was parasympathetic dominant, group II was sympathetic dominant, and group III consisted of parasympathetic-dominant subjects and controls who received only biofeedback of their own heart rates. The results corroborate three hypotheses: (1) subjects with para-sympathetic-dominant autonomic profiles perform in a way that is both qualitatively and quantitatively different from subjects with sympathetic-dominant autonomic profiles; (2) tests of interindividual variability yield data relevant to individual performance in visceral learning tasks; and (3) the combined use of autogenic training, biofeedback, and verbal feedback is suitable for conditioning large stable autonomic responses in humans.

  10. Operational Applications of Autogenic Feedback Training Exercise as a Treatment for Airsickness in the Military

    Science.gov (United States)

    Gebreyesus, Fiyore; Cowings, Patricia S.; Toscano, William B.

    2012-01-01

    Airsickness is experienced by about 50% of military aviators some time in their career. Aviators who suffer from recurrent episodes of airsickness are typically referred to the Naval Aerospace Medical Institute (NAMI) at Pensacola where they undergo extensive evaluation and 8 weeks of training in the Self-Paced Airsickness Desensitization (SPAD) program. Researchers at NASA Ames have developed an alternative mitigation training program, Autogenic Feedback Training Exercise (AFTE) that has demonstrated an 80% success rate for improving motion sickness tolerance.

  11. Inhaled dust and disease

    Energy Technology Data Exchange (ETDEWEB)

    Holt, P.F.

    1987-01-01

    This book discusses the following: the respiratory system; respirable dust; the fate of inhaled dust; translocation and some general effects of inhaled dust; silicosis; experimental research on silica-related disease; natural fibrous silicates; asbestos dust levels and dust sources; asbestos-related diseases - asbestosis, lung cancer, mesothelioma and other diseases, cancers at sites other than lung and pleura; experimental research relating to asbestos-related diseases; asbestos hazard - mineral types and hazardous occupations, neighbourhood and domestic hazard; silicates other than asbestos-man-made mineral fibres, mineral silicates and cement; metals; coal mine dust, industrial carbon and arsenic; natural and synthetic organic substances; dusts that provoke allergic alveolitis; tobacco smoke.

  12. Bone Substitutes for Peri-Implant Defects of Postextraction Implants

    Directory of Open Access Journals (Sweden)

    Pâmela Letícia Santos

    2013-01-01

    Full Text Available Placement of implants in fresh sockets is an alternative to try to reduce physiological resorption of alveolar ridge after tooth extraction. This surgery can be used to preserve the bone architecture and also accelerate the restorative procedure. However, the diastasis observed between bone and implant may influence osseointegration. So, autogenous bone graft and/or biomaterials have been used to fill this gap. Considering the importance of bone repair for treatment with implants placed immediately after tooth extraction, this study aimed to present a literature review about biomaterials surrounding immediate dental implants. The search included 56 articles published from 1969 to 2012. The results were based on data analysis and discussion. It was observed that implant fixation immediately after extraction is a reliable alternative to reduce the treatment length of prosthetic restoration. In general, the biomaterial should be used to increase bone/implant contact and enhance osseointegration.

  13. Synthesis of MgB2 at Low Temperature and Autogenous Pressure

    Directory of Open Access Journals (Sweden)

    Ian D. R. Mackinnon

    2014-05-01

    Full Text Available High quality, micron-sized interpenetrating grains of MgB2, with high density, are produced at low temperatures (~420 °C < T < ~500 °C under autogenous pressure by pre-mixing Mg powder and NaBH4 and heating in an Inconel 601 alloy reactor for 5–15 h. Optimum production of MgB2, with yields greater than 75%, occurs for autogenous pressure in the range 1.0 MPa to 2.0 MPa, with the reactor at ~500 °C. Autogenous pressure is induced by the decomposition of NaBH4 in the presence of Mg and/or other Mg-based compounds. The morphology, transition temperature and magnetic properties of MgB2 are dependent on the heating regime. Significant improvement in physical properties accrues when the reactor temperature is held at 250 °C for >20 min prior to a hold at 500 °C.

  14. Autogenous standard versus inside-out vein graft to repair facial nerve in rabbits

    Institute of Scientific and Technical Information of China (English)

    TANG Jie; WANG Xue-mei; HU Jing; LUO En; QI Meng-chun

    2008-01-01

    To evaluate autogenous vein grafts and inside-out vein grafts as conduits for the defects repair in the rabbit facial nerves.Methods:The 10 mm segments of buccal division of facial nerve were transected for 48 rabbits in this study.Then the gaps were immediately repaired by autogenous vein grafts or inside-out vein grafts in different groups. All the animals underwent the whisker movement test and electrophysiologic test during the following 16 weeks at different time points postoperatively. Subsequently,the histological examination was performed to observe the facial nerve regeneration morphologically.Results:At 8 weeks after operation,the facial nerve regeneration has significant difference between the experimental group and the control group in electrophysiologic test and histological observation. However,at the end of this study,16 weeks after operation,there was no significant difference between inside-out vein grafts and standard vein grafts in enhancing peripheral nerve regeneration.Conclusion:This study suggest that both kinds of vein grafts play positive roles in facial nerve regeneration after being repaired immediately,but the autogenous inside-out vein grafts might accelerate and facilitate axonal regeneration as compared with control.

  15. Differences in latent inhibition as a function of the autogenous-reactive OCD subtype.

    Science.gov (United States)

    Lee, Han-Joo; Telch, Michael J

    2010-07-01

    We examined differences in a visual search-based latent inhibition (LI) task in 48 non-treatment seeking individuals diagnosed with obsessive-compulsive disorder (OCD) and 26 non-OCD controls, using a visual search-based LI task as a function of participants' primary obsessional presentation based on the autogenous-reactive subtype model of obsessions (Lee & Kwon, 2003; Lee & Telch, 2007). We hypothesized that LI would be significantly attenuated among OCD participants whose primary obsessions were characterized by aversive impulses, images, or thoughts with sexual, aggressive, blasphemous, and repulsive themes (autogenous obsessions) due to their weakened attentional inhibitory mechanisms and elevated schizotypal personality features, as compared with those whose primary obsessions were characterized by somewhat realistic aversive mental intrusions about contamination, mistakes, accidents, or disarray (reactive obsession) and non-OCD controls. Results showed that those primarily displaying autogenous obsessions failed to display LI, whereas those primarily displaying reactive obsessions and non-OCD controls displayed significant LI effects. Our data suggest that the magnitude of LI varies as a function of primary obsessional presentations among individuals with OCD.

  16. Bone Biopsy

    Science.gov (United States)

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

  17. Chondroblastoma of the patella with aneurysmal bone cyst.

    Science.gov (United States)

    Tan, Honglue; Yan, Mengning; Yue, Bing; Zeng, Yiming; Wang, You

    2014-01-01

    Chondroblastoma of the patella is rare. Aneurysmal bone cysts, which develop from a prior lesion such as a chondroblastoma, are seldom seen in the patella. The authors report a case of a 36-year-old man who presented with 2 years of right knee pain without calor, erythema, pain on palpation, or abnormal range of motion. Radiological studies suggested aneurysmal bone cyst. The lesion was excised with curettage and the residual cavity filled with autogenous bone graft. Histopathology revealed chondroblastoma associated with a secondary aneurysmal bone cyst. In the follow-up period, the patient demonstrated normal joint activities with no pain. Normal configuration of the patella and bone union were shown on plain radiographs. The authors present a review of the literature of all cases of patellar chondroblastoma with aneurysmal bone cyst. This case is the 14th report of aneurysmal bone cyst arising in a chondroblastoma of the patella. According to the literature, computed tomography and magnetic resonance imaging are useful in the study of these lesions. The pathologic diagnosis is based on the presence of chondroblastoma and aneurysmal bone cyst. Treatment of this lesion includes patellectomy, curettage alone, and curettage with bone grafting. Despite the risk of recurrence of this lesion in the patella, the authors first recommend curettage followed by filling the cavity with bone graft. To protect the anterior tension of the patella intraoperatively, the bone window should be made at the medial edge of the patella to perform the curettage and bone grafting.

  18. Bone Densitometry (Bone Density Scan)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Bone Densitometry (DEXA) Bone densitometry, also called dual-energy ... limitations of DEXA Bone Densitometry? What is a Bone Density Scan (DEXA)? Bone density scanning, also called ...

  19. Minimal guided bone regeneration procedure for immediate implant placement in the esthetic zone

    Directory of Open Access Journals (Sweden)

    Nettemu Sunil Kumar

    2013-01-01

    Full Text Available The anterior maxilla presents a challenging milieu interior for ideal placement of implants because of the compromised bone quality. With the advent of intraoral bone harvesting and augmentation techniques, immediate implant placement into fresh extraction sockets have become more predictable. Immediate implant placement has numerous advantages compared to the delayed procedure including superior esthetic and functional outcomes, maintenance of soft and hard tissue integrity and increased patient compliance. This case report exhibits immediate implant placement in the maxillary esthetic zone by combining a minimal invasive autogenous block bone graft harvest technique for ensuring successful osseointegration of the implant at the extraction site.

  20. Chondroblastoma with secondary aneurysmal bone cyst of the hamate: case report.

    Science.gov (United States)

    Rhee, Peter C; Novais, Eduardo N; Shives, Thomas C; Shin, Alexander Y

    2012-03-01

    Chondroblastoma of the carpals is rare, can mimic other benign bone tumors, and presents a diagnostic challenge. There have been few cases of benign tumors involving the hamate, with only one reported case of chondroblastoma, which was treated with complete hamate excision. We present a case of chondroblastoma with secondary aneurysmal bone cyst of the hamate treated with curettage, high-speed burring, phenol, and autogenous iliac crest bone grafting. At the time of the most recent radiographic follow-up, there was full graft incorporation, preserved hamate morphology, and no evidence of recurrence.

  1. Histological Features and Biocompatibility of Bone and Soft Tissue Substitutes in the Atrophic Alveolar Ridge Reconstruction

    Directory of Open Access Journals (Sweden)

    Carlo Maiorana

    2016-01-01

    Full Text Available The reconstruction of the atrophic alveolar ridges for implant placement is today a common procedure in dentistry daily practice. The surgical reconstruction provides for the optimization of the supporting bone for the implants and a restoration of the amount of keratinized gingiva for esthetic and functional reasons. In the past, tissue regeneration has been performed with autogenous bone and free gingival or connective tissue grafts. Nowadays, bone substitutes and specific collagen matrix allow for a complete restoration of the atrophic ridge without invasive harvesting procedures. A maxillary reconstruction of an atrophic ridge by means of tissue substitutes and its histological features are then presented.

  2. Stem cell-mediated osteogenesis: therapeutic potential for bone tissue engineering

    Directory of Open Access Journals (Sweden)

    Neman J

    2012-03-01

    Full Text Available Josh Neman1, Amanda Hambrecht2, Cherie Cadry3, Rahul Jandial11Department of Neurosurgery, Beckman Research Institute, City of Hope National Cancer Center, Duarte, 2Department of Biological Sciences, University of Southern California, Los Angeles, 3Department of Public Health Sciences, University of California, Irvine, California, USAAbstract: Intervertebral disc degeneration often requires bony spinal fusion for long-term relief. Current arthrodesis procedures use bone grafts from autogenous bone, allogenic backed bone, or synthetic materials. Autogenous bone grafts can result in donor site morbidity and pain at the donor site, while allogenic backed bone and synthetic materials have variable effectiveness. Given these limitations, researchers have focused on new treatments that will allow for safe and successful bone repair and regeneration. Mesenchymal stem cells have received attention for their ability to differentiate into osteoblasts, cells that synthesize new bone. With the recent advances in scaffold and biomaterial technology as well as stem cell manipulation and transplantation, stem cells and their scaffolds are uniquely positioned to bring about significant improvements in the treatment and outcomes of spinal fusion and other injuries.Keywords: mesenchymal stem cell, osteogenesis, scaffolds, bone morphogenetic protein, Wnt, autograft, osteoblast

  3. A novel approach to human cranial tissue regeneration and frontal sinus obliteration with an autogenous platelet-rich/fibrin-rich composite matrix: 10 patients with a 6-10 year follow-up.

    Science.gov (United States)

    Mendonça-Caridad, Jose; Lopez, Pedro Juiz; Fayos, Francisco Vidal; Miery, Gustavo

    2013-06-01

    Advanced frontal sinus disease non-responsive to conservative therapy has been treated with fat obliteration for decades. More recently, a wide variety of autogenous, allogenic or synthetic materials have also been used. In this study we present a treatment based on totally autogenous procedures and materials that was successfully implemented in 10 patients and followed up for a period of 6-10 years, to evaluate the feasibility of a new approach for the treatment of frontal sinus disease and other related cranial osseous derangements, based on regenerative medicine as an alternative to fat or other obliterating or grafting materials. Platelet-rich and -poor plasma (PRP, PPP) are set to clot with cortical shavings from the skull surface. After surgically stimulating the sinus to encourage cell chemotaxis, migration and homing, the bioactive scaffold is placed and covered with a PPP membrane and a periosteal flap. Ten patients with pathologies ranging from devastating infection to invasive tumours or trauma were treated with this regenerative procedure in a single-stage surgery. All patients had an uneventful recovery with bone formation and no complications or recurrences over the years. The application of modern principles in tissue regeneration and wound healing has resulted in a favourable outcome, with no complications or sequelae, in a series of 10 patients with advanced frontal sinus disease over a long period of time.

  4. Nasal bone grafts from the removed hump used as overlay grafts to camouflage concave lateral crura.

    Science.gov (United States)

    Kubilay, Utku; Erdogdu, Suleyman; Sezen, Ozan Seymen

    2014-01-01

    Alar cartilage consists of a medial crus, middle crus and lateral crus. The lateral crus is an important aesthetic and functional structure of the nose. A 32-year-old male patient with concave lateral crura was operated by the authors. An open rhinoplasty with a dorsal approach to the septum is preferred. The nasal bones harvested from the hump, which is an autogenous graft trimmed and sutured on both concave lateral crura as an overlay camouflage grafts. Satisfactory result was achieved.

  5. Dust-off

    OpenAIRE

    Maycroft, Neil; Cheang, Shu Lea

    2015-01-01

    The fan of a motherboard switches on and off intermittently. It blows household dust, removed from the inside of a computer carcass, into the air. The dust then settles onto the motherboard, to be blown off again. This continual movement of dust is contained in the piece. However, it should remind us that the ceaseless creation and motion of unconfined dust accompanies all stages of the e-waste journey.

  6. Physics of interstellar dust

    CERN Document Server

    Krugel, Endrik

    2002-01-01

    The dielectric permeability; How to evaluate grain cross sections; Very small and very big particles; Case studies of Mie calculus; Particle statistics; The radiative transition probability; Structure and composition of dust; Dust radiation; Dust and its environment; Polarization; Grain alignment; PAHs and spectral features of dust; Radiative transport; Diffuse matter in the Milky Way; Stars and their formation; Emission from young stars. Appendices Mathematical formulae; List of symbols.

  7. Dust in the Universe

    Science.gov (United States)

    Hemenway, Mary Kay; Armosky, Brad J.

    2004-01-01

    Space is seeming less and less like empty space as new discoveries and reexaminations fill in the gaps. And, ingenuity and technology, like the Spitzer Space Telescope, is allowing examination of the far reaches of the Milky Way and beyond. Even dust is getting its due, but not the dust everyone is familiar with. People seldom consider the dust in…

  8. Frontalis Sling Operation using Silicone Rod Compared with Autogenous Fascia Lata for Simple Congenital Ptosis

    Directory of Open Access Journals (Sweden)

    Purnima Rajkarnikar Sthapit

    2014-09-01

    Full Text Available Introduction: To evaluate the cosmetic results and recurrence of unilateral frontalis sling surgery using a silicone rod compared with autogenous fascia lata in cases of simple congenital ptosis. Methods: This is a retrospective comparative study of 59 patients who underwent a frontalis sling operation for congenital ptosis. Patients were divided into two groups according to the sling material used; an autogeneous fascia lata (fl group (n = 24 and a silicone rod group (sl (n = 35. Cosmetic results and recurrence rates were compared between these 2 groups. The cosmetic results of the frontalis sling operation were assessed as good, fair, or poor based on the difference between the Margin Reflex Distance of both eyelids and graded as good if the difference in two eyes was ≤1mm and poor if it was 2mm or more. Recurrence was defined as the conversion of the cosmetic result from good or fair to poor category. Results: At postoperative day seven and 30, MRD of both the groups were good but on three months follow-up MRD of silicon rod group dropped, however it was not statistically significant .Lid contour was good in both the groups, however, lid symmetry was poor in two cases of fascia lata at three months follow-up. Repeat surgery for poor outcome was done in 8.6% of cases in silicon rod and 8.3% of fascia lata group. Conclusions: The frontalis sling operation using either a silicone rod or autogenous fascia lata showed equally good cosmetic results and lower recurrence rate at three months follow up. Keywords: congenital ptosis; fascia lata; frontalis sling surgery; margin reflex distance; silicone rod.

  9. Clinical and Histological Results of Vertical Ridge Augmentation of Atrophic Posterior Mandible with Inlay Technique of Cancellous Equine Bone Blocks

    Directory of Open Access Journals (Sweden)

    Pistilli R

    2013-12-01

    Full Text Available Aim: We want to evaluate a new bone block material in the inlay technique, for the vertical bone augmentation of a posterior atrophic mandible, in order to perfom aesthetic and prosthetic rehabilitation and enable implant insertion. Materials & Methods: Inlay technique and the subsequent successful implant rehabilitation in the atrophic right posterior mandible in a 42-year-old woman, was completed using a cancellous equine bone block as grafting material. Results: Three months after surgical procedure both clinical and histological aspects show complete integration of the biomaterial with the surrounding bone and three dental implants were placed. Computed tomography and conventional radiography showed a 5mm mean vertical bone gain. Conclusion: Cancellous equine bone grafts may be an effective alternative to autogenous bone and/or inorganic bovine bone for reconstruction of the posterior mandible using inlay technique.

  10. Autogenous control of PspF, a constitutively active enhancer-binding protein of Escherichia coli.

    OpenAIRE

    Jovanovic, G; Dworkin, J; Model, P

    1997-01-01

    Escherichia coli sigma54-dependent phage shock protein operon (pspA to -E) transcription is under the control of PspF, a constitutively active activator. Sigma70-dependent transcription of pspF is under autogenous control by wild-type PspF but not by a DNA-binding mutant, PspF deltaHTH. Negative autoregulation of PspF is continual and not affected by stimuli, like f1 pIV, that induce the pspA to -E operon. PspF production is independent of PspA (the negative regulator of the pspA to -E operon...

  11. Stepwise surgical approach to diabetic partial foot amputations with autogenous split thickness skin grafting

    Directory of Open Access Journals (Sweden)

    Crystal L. Ramanujam

    2016-06-01

    Full Text Available In the surgical treatment of severe diabetic foot infections, substantial soft tissue loss often accompanies partial foot amputations. These sizeable soft tissue defects require extensive care with the goal of expedited closure to inhibit further infection and to provide resilient surfaces capable of withstanding long-term ambulation. Definitive wound closure management in the diabetic population is dependent on multiple factors and can have a major impact on the risk of future diabetic foot complications. In this article, the authors provide an overview of autogenous skin grafting, including anatomical considerations, clinical conditions, surgical approach, and adjunctive treatments, for diabetic partial foot amputations.

  12. A thermal comparator sensor for measuring autogenous deformation in hardening Portland cement paste

    DEFF Research Database (Denmark)

    Østergaard, Thomas; Jensen, Ole Mejlhede

    2003-01-01

    of the thermal comparator is based on thermal expansion of aluminium. A particular characteristic of the measuring system is the fixation of the thermal comparator sensor to the deforming specimen. The modular system ensures effective thermostatic control of the hydrating cement paste samples. The technique......This paper describes a simple and accurate experimental device specially developed to measure autogenous deformation in hardening cement-based materials. The measuring system consists of a so-called thermal comparator sensor and a modular thermostatically controlled system. The operating principle...

  13. 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.

  14. Late sarcoma development after curettage and bone grafting of benign bone tumors

    Energy Technology Data Exchange (ETDEWEB)

    Picci, Piero, E-mail: piero.picci@ior.it [Bone Tumor Center, Istituto Ortopedico Rizzoli, Bologna (Italy); Sieberova, Gabriela [Dept. of Pathology, National Cancer Institute, Bratislava (Slovakia); Alberghini, Marco; Balladelli, Alba; Vanel, Daniel [Bone Tumor Center, Istituto Ortopedico Rizzoli, Bologna (Italy); Hogendoorn, Pancras C.W. [Dept. of Pathology, Leiden University Medical Center, Leiden (Netherlands); Mercuri, Mario [Bone Tumor Center, Istituto Ortopedico Rizzoli, Bologna (Italy)

    2011-01-15

    Background and aim: Rarely sarcomas develop in previous benign lesions, after a long term disease free interval. We report the experience on these rare cases observed at a single Institution. Patients and methods: 12 cases curetted and grafted, without radiotherapy developed sarcomas, between 1970 and 2005, 6.5-28 years from curettage (median 18, average 19). Age ranged from 13 to 55 years (median 30, average 32) at first diagnosis; tumors were located in the extremities (9 GCT, benign fibrous histiocytoma, ABC, and solitary bone cyst). Radiographic and clinic documentation, for the benign and malignant lesions, were available. Histology was available for 7 benign and all malignant lesions. Results: To fill cavities, autogenous bone was used in 4 cases, allograft in 2, allograft and tricalcium-phosphate/hydroxyapatite in 1, autogenous/allograft in 1, heterogenous in 1. For 3 cases the origin was not reported. Secondary sarcomas, all high grade, were 8 osteosarcoma, 3 malignant fibrous histiocytoma, and 1 fibrosarcoma. Conclusions: Recurrences with progression from benign tumors are possible, but the very long intervals here reported suggest a different cancerogenesis for these sarcomas. This condition is extremely rare accounting for only 0.26% of all malignant bone sarcomas treated in the years 1970-2005 and represents only 8.76% of all secondary bone sarcomas treated in the same years. This incidence is the same as that of sarcomas arising on fibrous dysplasia, and is lower than those arising on bone infarcts or on Paget's disease. This possible event must be considered during follow-up of benign lesions.

  15. Ortho- and heterotopic bone grafts in bifocal transport osteogenesis for craniofacial reconstruction--an experimental study in sheep.

    Science.gov (United States)

    Kramer, F-J; Mueller, M; Rahmstorf, M; Swennen, G R J; Dempf, R; Schierle, H

    2004-09-01

    Bifocal transport osteogenesis (BTO) is a promising technique for the reconstruction of extended osseous craniofacial defects. Aim of this study was to determine the potential of this technique related to various donor sites of the transport segment. In 10 adult sheep critical size defects of the calvaria were treated by gradual movement of a transport segment consisting either of autogenous regional free calvarial bone grafts (n=5) or autogenous illiac free bone grafts (n=5). Latency period was 5 days; the rate of distraction was 1mm per day and extended approximately 40 days. The consolidation period was 28 days. After harvesting, specimens were investigated by conventional radiography, CT-scans, histologically and by fluorescence. In both groups transport osteogenesis resulted in a complete closure of the critical size defect. Membranous bone formation and remodeling occurred during the entire period of distraction and consolidation. The volumes and thickness of newly formed bone at the defect site were increased significantly when calvarial bone grafts were used (P<0.05). Iliac bone grafts became progrediently smaller during distraction, while the volume of calvarial grafts remained relatively constant (P<0.05). In conclusion, transport segments consisting of calvarial and iliac bone resulted in a reliable closure of craniofacial critical size defects in adult organisms; the application of calvarial bone grafts resulted in an increased extend of bone formation.

  16. Toxicity of lunar dust

    CERN Document Server

    Linnarsson, Dag; Fubini, Bice; Gerde, Per; Karlsson, Lars L; Loftus, David J; Prisk, G Kim; Staufer, Urs; Tranfield, Erin M; van Westrenen, Wim

    2012-01-01

    The formation, composition and physical properties of lunar dust are incompletely characterised with regard to human health. While the physical and chemical determinants of dust toxicity for materials such as asbestos, quartz, volcanic ashes and urban particulate matter have been the focus of substantial research efforts, lunar dust properties, and therefore lunar dust toxicity may differ substantially. In this contribution, past and ongoing work on dust toxicity is reviewed, and major knowledge gaps that prevent an accurate assessment of lunar dust toxicity are identified. Finally, a range of studies using ground-based, low-gravity, and in situ measurements is recommended to address the identified knowledge gaps. Because none of the curated lunar samples exist in a pristine state that preserves the surface reactive chemical aspects thought to be present on the lunar surface, studies using this material carry with them considerable uncertainty in terms of fidelity. As a consequence, in situ data on lunar dust...

  17. An in vivo tracing study on bone marrow mesenchymal stem cells in rats exposed to silica dust%骨髓间充质干细胞在染矽尘大鼠体内示踪研究

    Institute of Scientific and Technical Information of China (English)

    周永梅; 黄明; 燕玲; 曾子芳; 吴奇峰; 梁伟辉; 曾小菁

    2015-01-01

    Objective To investigate the distribution of bone marrow mesenchymal stem cell ( BMMSC) in rats exposed to silica dust.Methods BMMSCs were isolated from 7 specific pathogen free healthy male SD rats through bone marrow adherent method and transfected using lentiviral vector-enhanced green fluorescence protein ( LV-eGFP ) .Then Trypan blue staining and CCK-8 were applied to assay the cellular survival rate and cell proliferation activity before and after transfection, while 8 rats of the same kind were randomly divided into control group and silicotic group, with 4 rats in each group.Silicotic group was injected intratracheally with 1.0 mL silica suspension ( mass concentration was 40 g/L) while control group was given 1.0 mL physiological sodium chloride solution.The transfected BMMSCs were intravenously injected into the caudal veins of rats of the two groups.The lung, liver, spleen, heart, kidney and brain were taken and observed under the fluorescence microscopy by frozen section 1, 2, 3 and 4 weeks respectively after transplantation.The fluorescence distribution and of BMMSCs transplanted with LV-eGFP were detected, the fluorescence intensity of every organ was calculated by Image-pro plus 6.0.Results When the multiplicity of infection was 50, the transfection efficiency of BMMSCs was 80.00%, the green fluorescence expression was powerful and sustained, and there was not any change found in morphological characteristics of BMMSC after transfection.The respective cellular survival rates had no statistical significant difference between transfected and untransfected BMMSCs with LV-eGFP [ ( 97.67 ±0.60 )% vs (98.03 ±0.56 )%, P >0.05 ] .Cell proliferation activity had no statistical significant difference in main effects of transfection treatment (P >0.05).In the first week after transplantation of BMMSCs transfected with LV-eGFP, the fluorescence expression was observed in tissue sections of each organ in rats of two groups, the stronger fluorescence was

  18. Rapid maxillary expansion in alveolar cleft repaired with a tissue-engineered bone in a canine model.

    Science.gov (United States)

    Huang, Jialiang; Tian, Bo; Chu, Fengting; Yang, Chenjie; Zhao, Jun; Jiang, Xinquan; Qian, Yufen

    2015-08-01

    This study aims to investigate the effects of orthodontic expansion on graft area of a tissue-engineered bone (TEB) BMSCs/β-TCP, and to find an alternative strategy for the therapy of alveolar cleft. A unilateral alveolar cleft canine model was established and then treated with BMSCs/β-TCP under rapid maxillary expansion (RME). Sequential fluorescent labeling, radiography and helical computed tomography were used to evaluate new bone formation and mineralization in the graft area. Hematoxylin-eosin staining and Van Gieson׳s picro fuchsin staining were performed for histological and histomorphometric observation. ALP activity, mineralization and the expression of osteogenic differentiation related genes of BMSCs that grew on the β-TCP scaffold were promoted by their cultivation in osteogenic medium. Based on fact, TEB was constructed. After 8 weeks of treatment with BMSCs/β-TCP followed by RME, new bone formation and mineralization of the dogs were markedly accelerated, and bone resorption was significantly reduced, compared with the untreated dogs, or those only treated with autogenous iliac bone. The treatment with both TEB and RME evidently made the bone trabecula more abundant and the area of bone formation larger. What is more, there were no significant differences between BMSCs/β-TCP group and the group treated with autogenous bone and RME. This study further revealed that TEB was not only a feasible clinical approach for patients with alveolar cleft, but also a potential substituent of autogenous bone, and its combination with RME might be an alternative strategy for the therapy of alveolar cleft.

  19. Treatment of an Immature Autogenous Arteriovenous Fistula with Percutaneous Transluminal Angioplasty

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyoung Rae [Kangwon National University, Chuncheon (Korea, Republic of)

    2008-11-15

    The purpose of this study was to evaluate the efficacy of percutaneous transluminal angioplasty (PTA) in facilitating maturation of autogenous arteriovenous fistulae. There were 12 immature autogenous arteriovenous fistulae. We performed 15 PTAs transvenously. Post-intervention anatomic and clinical successes were estimated, and the 6-month and 1-year primary and secondary patency rates were calculated using Kaplan-Meier analysis. All immature fistulae had underlying stenosis (n=20): arteriovenous anastomosis (n=1) and venous outflow (n=19): 1) within 5 cm from the anastomosis (n=10); 2) more than 5 cm but less than 10 cm from the anastomosis (n=5); 3) more than 10 cm from the anastomosis, including central veins (n=4). Six fistulae had two or more stenoses. Repeat intervention was necessary in two patients. The anatomical success rate was 94.3%, and the clinical success rate was 86.7%. The 6-month and 1-year primary patency rates were 72.7% and 54.5%, and the secondary patency rates were 100% and 81.8%, respectively. All immature hemodialysis fistulae have underlying stenosis, most of which are located near the arteriovenous anastomosis. Early interventional procedures are helpful in the salvage and maintenance of immature arteriovenous fistulae, with a high degree of success

  20. Autogenous tibial strut grafts used in severe kyphoscoliosis:surgical policies and preliminary results

    Institute of Scientific and Technical Information of China (English)

    CHEN Hui; QIU Yong; WANG Bin; YU Yang; ZHU Ze-zhang ZHU Li-hua

    2005-01-01

    Background Surgery for severe kyphoscoliosis is frequently unsatisfying because of loss of correction, high rate of pseudarthrosis and neurological complications.Several authors reported that the anterior fusion with strut grafts might improve the surgical outcome.This article describes and assesses the surgical strategies and the application of autogenous tibial strut in the treatment of severe kyphoscoliosis.Results The mean preoperative and postoperative kyphosis was 82°and 52°respectively, and the mean scoliosis was 84°and 44°respectively.Complications included pseudarthrosis (2 cases, one with graft fracture and the other with hook displacement), posterior elements fractures (4), pleura penetrations (3, in the plastic surgery of the thoracic cage), dura tear (2), exudative pleuritis (2, in the anterior surgery), and tibia fracture of the harvesting site (1).The mean loss of correction in coronal and sagittal plane was 6° and 7° respectively.Except for 1 case, the patients with incomplete paraplegia showed improvements to varying extents.Conclusion Autogenous tibial strut can provide excellent support to the kyphoscoliotic spine: it reduces pseudarthrodic rate, loss of correction and complications of graft harvest, it also prevents the occurrence of neurological impairment.

  1. Influence of the association between platelet-rich fibrin and bovine bone on bone regeneration. A histomorphometric study in the calvaria of rats.

    Science.gov (United States)

    Oliveira, M R; deC Silva, A; Ferreira, S; Avelino, C C; Garcia, I R; Mariano, R C

    2015-05-01

    This study aimed to investigate the effects of platelet-rich fibrin (PRF) associated or not with Bio-Oss on bone defects in the calvaria of rats. A critical-size defect of 5-mm diameter was performed in the calvaria of 48 rats. These animals were divided into six groups of eight animals each, according to the treatment received: homogeneous clot, autogenous clot, autogenous PRF, homogeneous PRF, Bio-Oss, or Bio-Oss associated with PRF. The animals were euthanized after 30 or 60 days. Bone regeneration was evaluated by histomorphometric analysis. The highest mean percentages of new bone formation at 30 days (54.05% ± 5.78) and 60 days (63.58% ± 5.78) were observed in the Bio-Oss associated with PRF group; in particular, the percentage of new bone at 30 days was significantly higher than that of all of the other groups (P<0.01). At 60 days, the Bio-Oss associated with PRF (63.58% ± 5.78) and Bio-Oss (57.34% ± 5.78) groups had similar results, and both showed a statistical difference compared to the other groups. PRF had a positive effect on bone regeneration only when associated with Bio-Oss.

  2. Operational Dust Prediction

    Science.gov (United States)

    Benedetti, Angela; Baldasano, Jose M.; Basart, Sara; Benincasa, Francesco; Boucher, Olivier; Brooks, Malcolm E.; Chen, Jen-Ping; Colarco, Peter R.; Gong, Sunlin; Huneeus, Nicolas; Jones, Luke; Lu, Sarah; Menut, Laurent; Morcrette, Jean-Jacques; Mulcahy, Jane; Nickovic, Slobodan; Garcia-Pando, Carlos P.; Reid, Jeffrey S.; Sekiyama, Thomas T.; Tanaka, Taichu Y.; Terradellas, Enric; Westphal, Douglas L.; Zhang, Xiao-Ye; Zhou, Chun-Hong

    2014-01-01

    Over the last few years, numerical prediction of dust aerosol concentration has become prominent at several research and operational weather centres due to growing interest from diverse stakeholders, such as solar energy plant managers, health professionals, aviation and military authorities and policymakers. Dust prediction in numerical weather prediction-type models faces a number of challenges owing to the complexity of the system. At the centre of the problem is the vast range of scales required to fully account for all of the physical processes related to dust. Another limiting factor is the paucity of suitable dust observations available for model, evaluation and assimilation. This chapter discusses in detail numerical prediction of dust with examples from systems that are currently providing dust forecasts in near real-time or are part of international efforts to establish daily provision of dust forecasts based on multi-model ensembles. The various models are introduced and described along with an overview on the importance of dust prediction activities and a historical perspective. Assimilation and evaluation aspects in dust prediction are also discussed.

  3. Modifications in Autogenous Rib Cartilage Reconstruction of Microtia%改良法肋软骨全耳廓再造术

    Institute of Scientific and Technical Information of China (English)

    李意源; 张如鸿; 张群; 许志成; 许枫; 李大涛; 孙楠; 汪诚

    2014-01-01

    Objective To introduce the modifications in autogenous rib cartilage reconstruction of microtia, so as to present more natural and stable morphology of the reconstructed ear. Methods From 2009, 234 cases of microtia were received modified total ear reconstruction by autogenous costal cartilage. Modifications of the two-staged surgery were as follows: Decreasing the needed rib cartilage into 6~8 in donor site;Different cartilage framework in different patient;Designing a U shape cartilage block to support the complex of tragus and antitragus; The negative suction management in the second stage surgery;Using specific bone cement in the second stage surgery for ear elevation. Results All the patients were followed up for more than 6 months, most reconstructed ears were satisfiable in symmetry and stability of the three dimensional morphology and the cranio-auricular angle. Skin color and texture were favorable as well. The most common complication was reduction of the projection angle of the constructed ear caused by hypertrophic scars and severe scar contractures. Conclusion These modifications in autogenous rib cartilage reconstruction of microtia are effective and practical. So far the results of ear reconstruction are satisfactory but not in complete control.%目的:对二期法的肋软骨全耳廓再造术进行改进,以增强再造耳结构的自然性及稳定性。方法自2009起,对234例小耳畸形患者行全耳廓再造,并对肋软骨全耳廓再造法进行了系列改良,措施包括:①供区仅切取第6~8肋软骨;②根据肋软骨厚度不同,采取个性化雕刻;③耳屏对耳屏复合体下方以U型软骨块支撑;④Ⅰ期术后,对耳舟和耳甲腔进行负压管理;⑤Ⅱ期手术时使用特定形状的骨水泥支架进行支撑。结果术后患者均随访6个月以上,在耳廓的位置及三维形态、耳廓皮肤色泽、与健侧耳的对称性等方面多能达到满意效果,再造耳结构及颅

  4. Decreased osteoblasts and increased osteoclasts in rats after coal dust exposure

    Directory of Open Access Journals (Sweden)

    Izaak Zoelkarnain Akbar

    2016-02-01

    Full Text Available Bone remodeling is a physiological process of cortical and trabecular bone reconstruction, with initial bone resorption, by osteoclasts and concurrent bone formation by osteoblasts. Oxidative stress due to coal dust exposure is not only found in the lungs, but also in the circulation or systemically. The aim of this study was to determine the effect of oxidative stress from coal dust exposure on the number of osteoblasts and osteoclasts in rats. In this experimental study, four groups were evaluated: control; coal dust exposure at 6.25 mg/m3 for 28 days; coal dust exposure at 12.5 mg/m3 for 28 days; coal dust exposure at 25 mg/m3 for 28 days (all exposures were given daily for one hour. Circulatory oxidative stress was measured by malondialdehyde level. Osteoblast and osteoclast numbers were counted by light microscopic examination of distal femoral cross-sections stained with hematoxylin eosin. This study showed that malondialdehyde levels were significantly increased in coal dust exposure groups, in comparison with the control group (p0.05. Coal dust exposure increased malondialdehyde level and osteoclast numbers, and decreased osteoblast numbers, but no correlation was found between oxidative stress (caused by coal dust exposure and osteoblast and osteoclast numbers.

  5. Bone Markers

    Science.gov (United States)

    ... markers may be seen in conditions such as: Osteoporosis Paget disease Cancer that has spread to the bone (metastatic bone disease) Hyperparathyroidism Hyperthyroidism Osteomalacia in adults and rickets in children—lack of bone mineralization, ...

  6. Bone scan

    Science.gov (United States)

    ... legs, or spine fractures) Diagnose a bone infection (osteomyelitis) Diagnose or determine the cause of bone pain, ... 2015:chap 43. Read More Broken bone Metabolism Osteomyelitis Review Date 12/10/2015 Updated by: Jatin ...

  7. Bone Cancer

    Science.gov (United States)

    Cancer that starts in a bone is uncommon. Cancer that has spread to the bone from another ... more common. There are three types of bone cancer: Osteosarcoma - occurs most often between ages 10 and ...

  8. Bone Diseases

    Science.gov (United States)

    Your bones help you move, give you shape and support your body. They are living tissues that rebuild constantly ... childhood and your teens, your body adds new bone faster than it removes old bone. After about ...

  9. Stone dusting process advance

    Energy Technology Data Exchange (ETDEWEB)

    Matt Ryan; David Humphreys [Mining Attachments (Qld.) Pty Ltd. (Australia)

    2009-01-15

    The coal mining industry has, for many years, used dry stone dust or calcium carbonate (CaCO{sub 3}) in the prevention of the propagation of coal dust explosions throughout their underground mines in Australia. In the last decade wet stone dusting has been introduced. This is where stone dust and water are mixed together to form a paste like slurry. This mixture is pumped and sprayed on to the underground roadway surfaces. This method solved the contamination of the intake airways but brought with it a new problem known as 'caking'. Caking is the hardened layer that is formed as the stone dust slurry dries. It was proven that this hardened layer compromises the dispersal characteristics of the stone dust and therefore its ability to suppress a coal dust explosion. This project set out to prove a specially formulated, non toxic slurry additive and process that could overcome the caking effect. The slurry additive process combines dry stone dust with water to form a slurry. The slurry is then treated with the additive and compressed air to create a highly vesicular foam like stone dusted surface. The initial testing on a range of additives and the effectiveness in minimising the caking effect of wet dusting were performed at Applied Chemical's research laboratory in Melbourne, Victoria and independently tested at the SGS laboratory in Paget, Queensland. The results from these tests provided the platform to conduct full scale spraying trials at the Queensland Mines Rescue Station and Caledon Coal's Cook Colliery, Blackwater. The project moved into the final stage of completion with the collection of data. The intent was to compare the slurry additive process to dry stone dusting in full-scale methane explosions at the CSIR Kloppersbos explosion facility in Kloppersbos, South Africa.

  10. Effect of platelet-rich plasma (PRP) concentration on the viability and proliferation of alveolar bone cells: an in vitro study.

    Science.gov (United States)

    Choi, B-H; Zhu, S-J; Kim, B-Y; Huh, J-Y; Lee, S-H; Jung, J-H

    2005-06-01

    Previous studies have shown that a combination of platelet-rich plasma (PRP) and autogenous bone graft can increase the rate of osteogenesis and enhance bone formation qualitatively. However, contradictory results were reported in a recent animal study. In order to clarify this inconsistency, this study examined the influence of the PRP concentrations on the viability and proliferation of alveolar bone cells in vitro. Bone cells obtained from the alveolar bone chips were exposed to various PRP concentrations. After a culture period of 7 days, cellular viability and proliferation were evaluated by counting the number of cells and a MTT assay. The results showed that the viability and proliferation of alveolar bone cells were suppressed by high PRP concentrations, but were stimulated by low PRP concentrations (1-5%). These in vitro results support the view that variations in the PRP concentrations might influence the bone formation within the PRP-treated bone grafts.

  11. Unicameral bone cyst of the lunate in an adult: case report

    Directory of Open Access Journals (Sweden)

    Alici Tugrul

    2010-10-01

    Full Text Available Abstract We report a case of a symptomatic unicameral (simple bone cyst of the lunate in a 42-year- old woman. The lesion was treated with curettage and cancellous autogenous iliac bone grafting. At five years of follow-up the wrist was pain free, there were no limitations of motion, and the radiographs showed complete obliteration of the cavity. To the best of our knowledge, no other unicameral bone cyst of the lunate has been reported in an adult. Cysts with significant cavities at the carpal bones in an adult should be approached cautiously, as they may require early curettage and bone grafting for healing, before collapse and degenerative changes occur.

  12. Measurement with corrugated tubes of early-age autogenous shrinkage of cement-based material

    DEFF Research Database (Denmark)

    Tian, Qian; Jensen, Ole Mejlhede

    2009-01-01

    The use of a special corrugated mould enables transformation of volume strain into horizontal, linear strain measurement in the fluid stage. This allows continuous measurement of the autogenous shrinkage of cement-based materials since casting, and also effectively eliminates unwanted influence...... on the measuring results from gravity, temperature variation and mould restraint. In this paper the principle of the corrugated tube measurement is described. A systematic study was carried out on the influence on the measuring results of the material properties, size effects and encapsulated air in the corrugated...... tube. The experimental results show that there is a minor influence on the measuring results of the stiffness and size of the plastic tube as well as of the encapsulated air. However, the influence decreases with the hardening process and becomes negligible a few hours after final set....

  13. Retrograde tracing of fluorescent gold after autogenous nerve transplantation on spinal cord injured in rats

    DEFF Research Database (Denmark)

    Lin, X; Liu, W; Ding, Ming;

    2016-01-01

    Objective To investigate the changes of the fluorescent gold retrograde tracing autogenous nerve transplantation on spinal cord injured in rats. Methods The animals were divided into two groups, with modified Allen impact method to establish model of spinal cord injury. After 4 weeks......, the transplantation group using autologous sural nerve graft to repair spinal cord injury period and non-transplantation group was only exposed incision without treatment. In the 4, 6 and 8 weeks after operation, the retrograde tracing of FG Fluoro-Gold was performed to discover the recovery of the axial plasma.......01). Conclusion After spinal cord injury, autologous nerve graft was repaired and survived well and promote the recovery of spinal cord injury segment shaft pulp transportation function....

  14. Autogenous wisdom tooth transplantation: A case series with 6-9 months follow-up

    Directory of Open Access Journals (Sweden)

    Tatjana Nimcenko

    2014-01-01

    Full Text Available Tooth transplantation can be considered a valid and predictable treatment option for rehabilitating young patients with permanent teeth loss. This study presents several cases of successful autogenous tooth transplantation with a 6-9 months follow-up. Tooth auto-transplantation can be considered a reasonable option for replacing missing teeth when a donor tooth is available. The auto-transplantation of a right mandibular third molar with compromised function and esthetics to replace the residual roots resulting from coronal destruction due to extensive carious lesion of the second molar in the same quadrant as shown in the presented cases can result a viable treatment alternative especially in a young patient that cannot undergo dental implant therapy. Transplantation of mature third molar seems to be a promising method for replacing a lost permanent molar tooth and restoring esthetics and function. This clinical procedure showed excellent functional and esthetical long-term results in the analyzed cases.

  15. Autogenous wisdom tooth transplantation: A case series with 6-9 months follow-up

    Science.gov (United States)

    Nimčenko, Tatjana; Omerca, Gražvydas; Bramanti, Ennio; Cervino, Gabriele; Laino, Luigi; Cicciù, Marco

    2014-01-01

    Tooth transplantation can be considered a valid and predictable treatment option for rehabilitating young patients with permanent teeth loss. This study presents several cases of successful autogenous tooth transplantation with a 6-9 months follow-up. Tooth auto-transplantation can be considered a reasonable option for replacing missing teeth when a donor tooth is available. The auto-transplantation of a right mandibular third molar with compromised function and esthetics to replace the residual roots resulting from coronal destruction due to extensive carious lesion of the second molar in the same quadrant as shown in the presented cases can result a viable treatment alternative especially in a young patient that cannot undergo dental implant therapy. Transplantation of mature third molar seems to be a promising method for replacing a lost permanent molar tooth and restoring esthetics and function. This clinical procedure showed excellent functional and esthetical long-term results in the analyzed cases. PMID:25540668

  16. Psychosomatic aspects in idiopathic infertility: effects of treatment with autogenic training.

    Science.gov (United States)

    O'Moore, A M; O'Moore, R R; Harrison, R F; Murphy, G; Carruthers, M E

    1983-01-01

    It has long been recognised that there is a relationship between emotional stress and some forms of infertility. We have endeavoured to estimate "stress' levels before and after Autogenic Training in 15 couples with infertility of at least two years' duration. Potential stress markers were: plasma prolactin, total urinary free cortisol and catecholamines, and four psychological tests: Spielberger State-Trait anxiety scale, Taylor Manifest Anxiety Scale, the Cattell 16 personality factor questionnaire, and the Eysenck Personality Questionnaire. A control group of ten normal couples was included for comparison. The biochemical finding of higher mean prolactin levels in the female patients vs their controls was of particular interest. The significant reduction of the prolactin level, in parallel with decreased anxiety scores following treatment, supports the hypothesis that the elevated prolactin levels in these patients are indeed linked with emotional stress.

  17. Effect of Cement Type on Autogenous Deformation of Cement-Based Materials

    DEFF Research Database (Denmark)

    Pietro, Lura; Ye, Guang; van Breugel, Klaas

    2004-01-01

    In this paper, measurements of non-evaporable water content, chemical shrinkage, autogenous deformation, internal relative humidity (RH), pore solution composition, and early-age elastic modulus are presented and discussed. All experiments were performed on Portland cement and blast-furnace slag...... (BFS) cement pastes. Self-desiccation shrinkage of the BFS cement paste was modeled based on the RH measurements, following the capillary-tension approach. The main findings of this study are: 1) self-desiccation shrinkage can be related to self-desiccation both for Portland and for BFS cement pastes......, taking into account the influence of the dissolved salts in the pore solution, 2) the BFS cement paste studied shows pronounced self-desiccation and self-desiccation shrinkage, mainly caused by its very fine pore structure....

  18. Autogenous shrinkage prediction on high-performance concrete of fly ash based on BP neural network

    Science.gov (United States)

    Wang, Baomin; Zhang, Wenping; Wang, Lijiu

    2006-11-01

    The article adopts test data of neural network for autogenous shrinkage to train and predict on the data which doesn't join training. The article's prediction is on the basis of common medium sand, 5-31.5mm limestone rubble, second class fly-ash, P.O42.5 silicate cement, considering factors include five ones such as ratio of water and cement, sand rate, content of cement, content of fly ash, etc.By adjusting various parameters of neural network structure, it obtains three optimized results of neural network simulation. The error between concrete autogtenous shrinkage value of neural network prediction and trial value is within 3%, which can meet requirement of the concrete engineering.

  19. Autogenic-feedback training: A preventive method for space adaptation syndrome

    Science.gov (United States)

    Cowings, Patricia S.; Sharp, Joseph C.; Toscano, William B.; Kamiya, Joe; Miller, Neal E.

    1987-01-01

    The progress made to date on the reduction of data for Spacelab 3 Shuttle experiment, No. 3AFT23 is reported. Four astronauts participated as subjects in this experiment. Crewmen A and B served as treatment subjects (i.e., received preflight training for control of their own motion sickness symptoms) and Crewmen C and D served as control (i.e., did not receive training). A preliminary evaluation of Autogenic Feedback Training (AFT) was made from visual inspections of graphs that were generated from the preflight and inflight and inflight physiological data which included: (1) Baseline rotating chair tests for all crewmen; (2) Posttraining rotating chair tests of treatment groups subjects; (3) Preflight data from Joint Integrated Simulations for all crewmen; and (4) Flight data for all crewmen during mission days 0 through 4, and mission day 6 for treatment subjects only. A summary of the findings suggested by these data is outlined.

  20. Effect of Autogenous Arc Welding Processes on Tensile and Impact Properties of Ferritic Stainless Steel Joints

    Institute of Scientific and Technical Information of China (English)

    A K Lakshminarayanan; K Shanmugam; V Balasubramanian

    2009-01-01

    The effect of autogeneous arc welding processes on tensile and impact properties of ferritic stainless steel conformed to AISI 409M grade is studied.Rolled plates of 4 mm thickness have been used as the base material for preparing single pass butt welded jointa.Tensile and impact properties,microhardness,microstructure,and fracture surface morphology of continuous current gas tungsten arc welding (CCGTAW),pulsed current gas tungsten arc welding (PCGTAW),and plasma arc welding (PAW) joints are evaluated and the results are compared.It is found that the PAW joints of ferritic stainless steel show superior tensile and impact properties when compared with CCGTAW and PCGTAW joints,and this is mainly due to lower heat input,finer fusion zone grain diameter,and higher fusion zone hardness.

  1. Comparison of Bone Resorption Rates after Intraoral Block Bone and Guided Bone Regeneration Augmentation for the Reconstruction of Horizontally Deficient Maxillary Alveolar Ridges.

    Science.gov (United States)

    Gultekin, B Alper; Bedeloglu, Elcin; Kose, T Emre; Mijiritsky, Eitan

    2016-01-01

    Purpose. Bone atrophy after tooth loss may leave insufficient bone for implant placement. We compared volumetric changes after autogenous ramus block bone grafting (RBG) or guided bone regeneration (GBR) in horizontally deficient maxilla before implant placement. Materials and Methods. In this retrospective study, volumetric changes at RBG or GBR graft sites were evaluated using cone-beam computed tomography. The primary outcome variable was the volumetric resorption rate. Secondary outcomes were bone gain, graft success, and implant insertion torque. Results. Twenty-four patients (28 grafted sites) were included (GBR, 15; RBG, 13). One patient (RBG) suffered mucosal dehiscence at the recipient site 6 weeks after surgery, which healed spontaneously. Mean volume reduction in the GBR and RBG groups was 12.48 ± 2.67% and 7.20 ± 1.40%, respectively. GBR resulted in significantly more bone resorption than RBG (P 0.05). Conclusions. Both RBG and GBR hard-tissue augmentation techniques provide adequate bone graft volume and stability for implant insertion. However, GBR causes greater resorption at maxillary augmented sites than RBG, which clinicians should consider during treatment planning.

  2. The use of a polycaprolactone-tricalcium phosphate scaffold for bone regeneration of tooth socket facial wall defects and simultaneous immediate dental implant placement in Macaca fascicularis.

    Science.gov (United States)

    Goh, Bee Tin; Chanchareonsook, Nattharee; Tideman, Henk; Teoh, Swee Hin; Chow, James Kwok Fai; Jansen, John A

    2014-05-01

    Bone regeneration and aesthetic outcomes may be compromised when immediate implants are placed at extraction sites with dehiscence defects. The aim of this study was to compare, in a monkey model, peri-implant bone regeneration and implant stability after immediate implant placement into tooth sockets with facial wall defects in two treatment groups. In eight control monkeys, the bony defect was reconstructed with autogenous particulate bone, whereas in 10 test monkeys a polycaprolactone-tricalcium phosphate (PCL-TCP) scaffold was used. The monkeys were sacrificed after 6 months and the specimens were analyzed by histology and histomorphometry. Better maintenance of facial bone contour was noted in the test group; however, bone regeneration was seen only at areas adjacent to a bony wall of the defect. The mean bone-to-implant contact was 27.6 ± 19.1% (control group) versus 6.8 ± 7.9% (test group). The mean bone area percentage was 11.8 ± 10.1% (control group) versus 6.8 ± 6.9% (test group). Implant survival was 100% at 6 months for both the groups. It was concluded that although the use of a PCL-TCP scaffold showed better maintenance of the alveolar contour as compared to autogenous particulate bone at 6 months, there was minimal bone regeneration within the defect.

  3. Galactic dust properties

    Science.gov (United States)

    Paradis, D.

    2011-12-01

    Recent studies have shown evidence for variations in the dust emissivity law with temperature and wavelength. A recent dust emission model, called TLS model (for two-level systems), based on the description of the disordered internal structure of the amorphous dust grains has been developped to interpret observations in the far-infrared/submillimeter (FIR/submm) domain. A recent work focusing on the comparison between data of the diffuse interstellar medium seen by FIRAS-WMAP, as well as Archeops compact sources, with the TLS model allowed us to constrain the model parameters characterizing the general Galactic dust properties. Using the newly available Herschel/Hi-GAL data of the inner Galactic plane, we report a 500 μm emissivity excess in the peripheral parts of the Galactic plane, that can reach up to 20% of the emissivity. Results of the TLS modeling indicate significant changes in the dust properties from the central to peripheral parts of the Galactic plane.

  4. The use of bovine screws to promote bone formation using a tibia model in dogs

    Science.gov (United States)

    Bianchini, Marco Aurélio; Pontual, Marco Antônio B; Bez, Leonardo; Benfatti, César Augusto M; Boabaid, Fernanda; Somerman, Martha J; Magini, Ricardo S

    2013-01-01

    The objective of this study was to evaluate the use of a unique resorbable bovine bone screw, to stimulate bone formation. Bovine bone screws were inserted in the tibia beagle dogs. Each animal received 8 screws, divided into Groups A (screws + no membranes), B (screws + titanium reinforced membranes) and C (bone defects treated with autogenous bone grafts). Animals were sacrificed at 2, 4 and 6 months. New bone was measured with a periodontal probe and reported an average of 7.4 mm in vertical bone gain for Group B, 3.6 mm for Group A and 1.7 mm for Group C. Submission to Kruskal-Wallis test showed statistical differences between groups (p<0,05). Histological examination revealed an intimate contact between the newly formed bone and the resorbing bone screws. Conclusion: Bovine bone screws provide environment for new bone formation and thus may provide an alternative therapy for enhancing bone formation vertically, including for regenerative procedures as well as prior to implant therapy. PMID:23058228

  5. Giant cell tumor of bone: Multimodal approach

    Directory of Open Access Journals (Sweden)

    Gupta A

    2007-01-01

    Full Text Available Background: The clinical behavior and treatment of giant cell tumor of bone is still perplexing. The aim of this study is to clarify the clinico-pathological correlation of tumor and its relevance in treatment and prognosis. Materials and Methods: Ninety -three cases of giant cell tumor were treated during 1980-1990 by different methods. The age of the patients varied from 18-58 yrs with male and female ratio as 5:4. The upper end of the tibia was most commonly involved (n=31, followed by the lower end of the femur(n=21, distal end of radius(n=14,upper end of fibula (n=9,proximal end of femur(n=5, upper end of the humerus(n=3, iliac bone(n=2,phalanx (n=2 and spine(n=1. The tumors were also encountered on uncommon sites like metacarpals (n=4 and metatarsal(n=1. Fifty four cases were treated by curettage and bone grafting. Wide excision and reconstruction was performed in twenty two cases . Nine cases were treated by wide excision while primary amputation was performed in four cases. One case required only curettage. Three inaccessible lesions of ilium and spine were treated by radiotherapy. Results: 19 of 54 treated by curettage and bone grafting showed a recurrence. The repeat curettage and bone grafting was performed in 18 cases while amputation was done in one. One each out of the cases treated by wide excision and reconstruction and wide excision alone recurred. In this study we observed that though curettage and bone grafting is still the most commonly adopted treatment, wide excision of tumor with reconstruction has shown lesser recurrence. Conclusion: For radiologically well-contained and histologically typical tumor, curettage and autogenous bone grafting is the treatment of choice . The typical tumors with radiologically deficient cortex, clinically aggressive tumors and tumors with histological Grade III should be treated by wide excision and reconstruction.

  6. Autogenous grafts for condylar reconstruction in treatment of TMJ ankylosis: current concepts and considerations for the future.

    Science.gov (United States)

    Khadka, A; Hu, J

    2012-01-01

    Temporomandibular joint (TMJ) ankylosis is characterized by difficulty or inability to open the mouth due to fusion of the temporal and the mandible, resulting in facial symmetry/deformity, malocclusion and dental problems. The only treatment option for TMJ ankylosis is surgical with or without condylar reconstruction. Various autogenous grafts are available for condylar reconstruction after freeing the ankylotic mass such as costochondral, sternoclavicular, fibular, coronoid, and metatarsophalangeal. Costochondral graft is preferred by surgeons, but distraction osteogenesis is slowly gaining popularity and may ultimately become the standard procedure, providing a cost-effective approach with low morbidity and excellent functional outcomes. Tissue engineering is another budding field which has shown promising results in animal studies but has not been applied to humans. To date, there is no ideal autogenous graft for condylar reconstruction that satisfies the complex anatomy and the myriad of functions of a missing condyle.

  7. 不同方式移植骨髓间充质干细胞在染矽尘大鼠体内的归巢%In vivo homing of bone marrow mesenchymal stem cells transplanted through different ways in rats exposed to silica dust

    Institute of Scientific and Technical Information of China (English)

    黄明; 周永梅; 燕玲; 李斌; 吴奇峰; 梁伟辉

    2015-01-01

    背景:骨髓间充质干细胞植入染矽尘大鼠体内能归巢到受损肺部,但何种植入途径在体内的归巢效果更好尚不清楚。  目的:动态比较观察不同途径移植骨髓间充质干细胞在染矽尘大鼠体内的分布情况。  方法:全骨髓贴壁法分离、培养供体大鼠骨髓间充质干细胞,用携带增强型绿色荧光蛋白基因的慢病毒(Lv-eGFP)转染骨髓间充质干细胞。受体大鼠用气管内注入法染尘,再随机分为经静脉组和经气管组,将转染Lv-eGFP的骨髓间充质干细胞分别经静脉、气管途径注入大鼠体内,在移植后的第1,2,3,4周处死大鼠,取心、肝、脾、肺、肾、脑组织进行冰冻切片,荧光显微镜下观察荧光,图文分析软件计算荧光强度。  结果与结论:两组大鼠肺组织均可见强烈、分布广泛且持续的绿色荧光,尤以气管、血管周围明显;两组荧光强度均随时间延长呈轻度减低趋势,但两组每周的荧光强度差异无显著性意义(P>0.05)。两组大鼠其余各脏器早期也均可见荧光,其中肝、脾、心脏组织荧光强、分布广,肾、脑组织荧光相对较弱、分布较稀疏;随时间推移,各组织荧光均逐渐减弱,面积逐渐减少,到后期仅肝、脾组织可见到较弱、散在荧光分布,脑组织荧光几乎不可见。在同一时间点,两组除第1周脑组织荧光强度差异有显著性意义(P0.05)。提示骨髓间充质干细胞经静脉和气管两种途径植入染矽尘大鼠体内归巢至受损肺部的效率相当。%BACKGROUND:Bone marrow mesenchymal stem cel s transplanted into rats exposed to silica dust can home to the injured lung, but the homing effects via different ways are stil unclear. OBJECTIVE:To comparatively observe the distribution of bone marrow mesenchymal stem cel s transplanted via different ways into rats exposed to silica dust. METHODS:Bone marrow

  8. 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 ...

  9. 自体脂肪移植治疗川字纹%Autogenous Fat Grafting for Glabellar Wrinkles

    Institute of Scientific and Technical Information of China (English)

    祝联; 李丹

    2012-01-01

    Objective To explore the effect of local autogenous fat grafting for glabellar wrinkles. Methods From September 2010 to April 2012, autogenous fat was grafted in sub-dermis of glabellar wrinkles in 8 cases. The transferee! fat strengthened the local skin tension, and made the wrinkle expand and smooth. Results Three months after autogenous fat grafting, glabellar wrinkles were disappeared in all cases with local smooth skin Left. The wrinkle was reappeared in half a year only in one case. Conclusion Local autogenous fat grafting could provide suspension and filling for the specific kind of glabellar wrinkles, and this method is simple, safe and effective,%目的 探索自体脂肪移植治疗川字纹的临床疗效.方法 201O年9月至2012年4月,对8例川字纹患者的累及皮肤区域内进行真皮下自体脂肪注射,提升局部皮肤张力.结果 8例川字纹患者均随访1年,自体脂肪移植3个月后川字纹皱折消失,局部皮肤平坦;6个月后只有1例患者川字纹复发.结论 对于特定类型的川字纹,局部自体脂肪移植可使得发生皱折的皮肤得到充填和支撑,本方法操作简便、安全,疗效良好.

  10. Comparison of lyophilization, and freezing in honey as techniques to preserve cortical bone allografts used to repair experimental femoral defects in domestic adult cats

    Directory of Open Access Journals (Sweden)

    M.P. Ferreira

    2012-04-01

    Full Text Available Cats with orthopedic conditions are a prominent part of the clinical work of veterinary. Conditions such as comminuted fractures, bone tumors and non-unions are often difficult to repair and may require the use of bone grafts for treatment. This study evaluated cortical bone allografts preserved in honey, frozen or lyophilized for correcting long bone defects created in the diaphysis of the right femur of domestic cats (n=24. In the control group (n=6, the defect was repaired using autogenous cortical bone graft. In the remaining animals (n=6/group, the defect was repaired with cortical bone allografts preserved in honey, frozen or lyophilized. Success of graft incorporation and length of time for consolidation were assessed through clinical, radiographic and histological evaluations performed up to 180 days. In the control, frozen, honey and lyophylized groups, respectively, success of graft incorporation was 91.6%, 83.3%, 75%, and 25%, with corresponding mean length of time for consolidation of 83.1, 78, 105 and 120 days. Incorporation percentage in the lyophilized group was significantly lower than in the frozen and control groups. In conclusion, bone grafts preserved in honey or frozen were effective for repairing cortical defects in the femurs of cats as compared to autogenous cortical bone grafts.

  11. Mechanisms of metal dusting corrosion

    DEFF Research Database (Denmark)

    Hummelshøj, Thomas Strabo

    In this thesis the early stages of metal dusting corrosion is addressed; the development of carbon expanded austenite, C, and the decomposition hereof into carbides. Later stages of metal dusting corrosion are explored by a systematic study of stainless steel foils exposed to metal dusting...... influence of oxygen and carbon on the metal dusting corrosion is explored. The results indicate that exposure to metal dusting conditions have a detrimental effect on the resistance against oxidation and, conversely, that exposure to oxidation has a detrimental effect on the resistance towards metal dusting....... Consequently, a combination of carburizing and oxidizing conditions has a strong mutual catalyzing effect on the metal dusting corrosion....

  12. Bone marrow aspiration

    Science.gov (United States)

    Iliac crest tap; Sternal tap; Leukemia - bone marrow aspiration; Aplastic anemia - bone marrow aspiration; Myelodysplastic syndrome - bone marrow aspiration; Thrombocytopenia - bone marrow aspiration; Myelofibrosis - bone marrow aspiration

  13. Wrapped omentum with periosteum concurrent with adipose derived adult stem cells for bone tissue engineering in dog model.

    Science.gov (United States)

    Sadegh, Amin Bigham; Basiri, Ehsan; Oryan, Ahmad; Mirshokraei, Pezhman

    2014-03-01

    Adipose derived adult stem cells (ASCs) are multipotent cells that are able to differentiate into osteoblasts in presence of certain factors. The histological characteristics of periosteum makes it a specific tissue with a unique capacity to be engineered. Higher flexibility of the greater omentum is useful for reconstructive surgery. These criteria make it suitable for tissue engineering. The present study was designed to evaluate bone tissue engineering with periosteal free graft concurrent with ASCs and pedicle omentum in dog model. Twelve young female indigenous dogs were used in this experiment. In omental group (n = 4), end of omentum was wrapped by periosteum of the radial bone in abdomen of each dog. In omental-autogenously ASCs group (n = 4), 1 ml of ASCs was injected into the wrapped omentum with periosteum while in omental-allogenously ASCs group (n = 4), 1 ml of allogenous ASCs was injected. Lateral view radiographs were taken from the abdominal cavity postoperatively at the 2nd, 4th, 6th and 8th weeks post-surgery. Eight weeks after operation the dogs were re-anesthetized and the wrapped omenum by periosteum in all groups was found and removed for histopathological evaluation. Our results showed that omentum-periosteum, omental-periosteum-autogenous ASCs and omental-periosteum-allogenous ASCs groups demonstrated bone tissue formation in the abdominal cavity in dog model. The radiological, macroscopical and histological findings of the present study by the end of 8 weeks post-surgery indicate bone tissue engineering in all three groups in an equal level. The present study has shown that the wrapped omentum with periosteum concurrent with ASCs (autogenous or allogenous ASCs) lead to a favorable bone tissue formation. We suggested that it may be useful when pedicle graft omentum used concurrent with periosteum in the bone defect reconstruction, and this phenomenon should be studied in future.

  14. Nano Dust Analyzer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a new highly sensitive instrument to confirm the existence of the so-called nano-dust particles, characterize their impact parameters, and...

  15. Composite circumstellar dust grains

    Science.gov (United States)

    Gupta, Ranjan; Vaidya, Dipak B.; Dutta, Rajeshwari

    2016-10-01

    We calculate the absorption efficiencies of composite silicate grains with inclusions of graphite and silicon carbide in the spectral range 5-25 μm. We study the variation in absorption profiles with volume fractions of inclusions. In particular we study the variation in the wavelength of peak absorption at 10 and 18 μm. We also study the variation of the absorption of porous silicate grains. We use the absorption efficiencies to calculate the infrared flux at various dust temperatures and compare with the observed infrared emission flux from the circumstellar dust around some M-type and asymptotic giant branch stars obtained from IRAS and a few stars from Spitzer satellite. We interpret the observed data in terms of the circumstellar dust grain sizes, shape, composition and dust temperature.

  16. Composite Circumstellar Dust Grains

    CERN Document Server

    Gupta, Ranjan; Dutta, Rajeshwari

    2016-01-01

    We calculate the absorption efficiencies of composite silicate grains with inclusions of graphite and silicon carbide in the spectral range 5--25$\\rm \\mu m$. We study the variation in absorption profiles with volume fractions of inclusions. In particular we study the variation in the wavelength of peak absorption at 10 and 18$\\rm \\mu m$. We also study the variation of the absorption of porous silicate grains. We use the absorption efficiencies to calculate the infrared flux at various dust temperatures and compare with the observed infrared emission flux from the circumstellar dust around some M-Type \\& AGB stars obtained from IRAS and a few stars from Spitzer satellite. We interpret the observed data in terms of the circumstellar dust grain sizes; shape; composition and dust temperature.

  17. Randomized controlled analysis-autogenous bone peg graft improved offset hemiarthroplasty in high risk patients: a novel cost effective technique

    Directory of Open Access Journals (Sweden)

    Hashmukh Shantilal Varma

    2016-06-01

    Results: In patients with novel technique value of X was 1 mm+/-0.8 SD, whereas value of X in conventional technique the value of X was significantly higher of about 7.2 mm+/-1.6 SD and this was associated with increased femoral off set 47.2+/-2.0 SD and the correlation was found to be statistically significant (p<0.05. Furthermore, in group B where graft was not used subsidence was found in 6 patients (24%. None was revised during the period of follow up. Conclusions: Our preliminary results indicate that the approach proposed is feasible and effective in the management of intracapsular fracture neck femur in high risk patients with unipolar prosthesis. [Int J Res Med Sci 2016; 4(6.000: 1897-1902

  18. Volumetric changes of the graft after maxillary sinus floor augmentation with Bio-Oss and autogenous bone in different ratios

    DEFF Research Database (Denmark)

    Jensen, Thomas; Schou, Søren; Svendsen, Patricia Anne

    2012-01-01

    composition was selected at random and placed concomitant with implant placement. Computed tomographies of the maxillary sinuses were obtained preoperatively, immediately postoperatively, and at euthanasia after 12 weeks. The volumetric changes of the graft were estimated using the Cavalieri principle...

  19. Dust Versus Cosmic Acceleration

    CERN Document Server

    Aguirre, A N

    1999-01-01

    Two groups have recently discovered a statistically significant deviation in the fluxes of high-redshift type Ia supernovae from the predictions of a Friedmann model with zero cosmological constant. This letter argues that bright, dusty, starburst galaxies would preferentially eject a dust component with a shallower opacity curve (hence less reddening) and a higher opacity/mass than the observed galactic dust which is left behind. Such dust could cause the falloff in flux at high-z without violating constraints on reddening or metallicity. The specific model presented is of needle-like dust, which is expected from the theory of crystal growth and has been detected in samples of interstellar dust. Carbon needles with conservative properties can supply the necessary opacity, and would very likely be ejected from galaxies as required. The model is not subject to the arguments given in the literature against grey dust, but may be constrained by future data from supernova searches done at higher redshift, in clust...

  20. Culture of osteoblasts on bio-derived bones

    Institute of Scientific and Technical Information of China (English)

    LAN Xu; YANG Zhi-ming; GE Bao-feng; LIU Xue-mei

    2005-01-01

    Objective: To study the effect of bio-derived bones, as substitutes of autogenous bone grafts and demineralized cadaver bones, on the attachment, spreading and proliferation of isolated osteoblasts. Methods: Osteoblasts were isolated from the calvaria of a fetal rabbit through sequential collagenase digestion. In the attachment study, the osteoblasts labeled with 3H-leucine were incubated with the bio-derived bone materials in sterile microcentrifugale tubes for 15, 90 and 180 minutes, and 24 hours, respectively. The attached cells were collected and the radioactivity was measured with liquid scintillation spectrometry. In the proliferation study, the osteoblasts were cultured with the bio-derived bone materials for 24 hours and 3H-thymidine was added during the last 2 hours of the incubation. The attached cells were collected and the radioactivity was measured with liquid scintillation spectrometry. Osteoblasts were seeded on the bone graft materials for 60 or 120 minutes, 24 or 48 hours, and 3 or 7 days, then the co-culture was processed for scanning electron microscopy to observe the interaction of osteoblasts and the bio-derived bone materials. Results: Osteoblasts attached to the bio-derived bone materials in a time-dependent manner. There were significantly (P<0.05) more attached cells after 180 minutes than after 15 and 90 minutes of incubations (P<0.05). Osteoblasts were proliferated in a large amount on the surface and in the materials. Osteoblasts seeded onto 100 mg bio-derived bones resulted in significantly (P<0.05) more measurable proliferation than those seeded onto 10 mg bones. Osteoblasts appeared round as they attached to the materials, then flattened and spread over with time passing. Conclusions: Bio-derived bones can provide a good environment for the attachment and proliferation of osteoblasts.

  1. Ultrasonography-guided Balloon Angioplasty in an Autogenous Arteriovenous Fistula: Preliminary Results

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Chang [Daejeon St Mary' s Hospital, Daejeon (Korea, Republic of); Cho, June Sik [Chungnam National University College of Medicine, Daejeon (Korea, Republic of)

    2007-09-15

    Percutaneous trasnluminal angioplasty (PTA) of a malfunctioning arteriovenous fistula (AVF) in hemodialysis patients requires the use of contrast angiography and fluoroscopy guidance. We attempted to perform this procedure under duplex ultrasound guidance to reduce the amount of contrast agent administered and to reduce the radiation dose during the interventional procedures. From September 2006 to February 2007, 45 patients received interventional treatment due to malfunctioning hemodialysis access in our hospital. Among the patients, we selected 10 patients diagnosed with stenosis of an autogenous arteriovenous fistula based on a physical examination. There were six males and four females aged 51-78 years (mean age, 59 years). Seven of these patients had a Brescia-Cinimo type fistula and three patients had a basilic vein transposition. All procedures were performed in the angiography suite. All procedures that required angioplasty were performed under duplex ultrasound guidance and then contrast angiography was performed to confirm the final patency of the vessels. Conventional angioplasty was also performed under fluoroscopy guidance for any lesions that required an additional angioplasty. The volume flow before and after the PTA and procedure time were recorded. Clinical success was defined as the performance of one or more successful hemodialysis sessions after treatment. Eight of ten patients did not require an additional angioplasty by conventional angiography after the duplex- guided angioplasty. One case showed recoiling of stenosis after the duplex-guided PTA and another case was missed at duplex scanning due to the extremely short nature of the recoiling of stenosis. The mean volume flow before and after PTA was 167 ml/min (range, 80-259 ml/min) and 394.2 ml/min (range, 120-586 ml/min), respectively. No complications associated with the duplex-guide procedure occurred. In nine cases, PTA enabled hemodialysis to be conducted more than one time. In one

  2. A modified technique of four-bone fusion for advanced carpal collapse (SLAC/SNAC wrist).

    Science.gov (United States)

    Garcia-López, A; Perez-Ubeda, M J; Marco, F; Molina, M; López-Duran, L

    2001-08-01

    This study reports the outcome of 16 patients treated with a modified four-bone fusion for symptomatic stage II and III advanced carpal collapse. The technique is based on fusion of the capitate, lunate, hamate and triquetrum using an autogenous corticocancellous bone-graft fixed with screws. The void left behind after scaphoid excision was filled with an extensor carpi radialis longus anchovy. After an average follow up of 3 years; there were 13 excellent and three good outcomes. In every patient pain relief was achieved with preservation of joint motion and grip strength. All the patients were able to return to their previous activities and jobs. Radiographic evaluation showed bone fusion in all 16 patients with a slight decrease in carpal height but a well preserved radiolunate joint space. In conclusion, this technique provides immediate stable fixation and early mobilization and assures bone fusion.

  3. The effect of Emdogain gel on periodontal regeneration in autogenous transplanted dog′s teeth

    Directory of Open Access Journals (Sweden)

    Manuel Marques Ferreira

    2014-01-01

    Full Text Available Aim: The aim of this study was to assess the enamel matrix derivative (EMD as biomaterial used in autogenous tooth transplantation. Material and Methods: The study consisted of 3 beagle dogs, 5 months old, in which six incisors and six premolars were transplanted to mechanically prepared recipient alveolar sockets. One group of teeth was transplanted to a recipient bed, with EMD in the root surface. The second groups of teeth were transplanted using saline solution in the root surface. Every week, clinical examinations were done. Nine weeks later, the animals were killed and the specimens decalcified and prepared for histological and imunohistochemical analysis. Periodontal healing was evaluated by undertaking histomorphometric investigation and analyzed using the Mann- Whitney test (P = 0.05. Results: In both groups, all the transplanted teeth survived. Between the experimental groups, there was statistically significant difference in the complete healing (P = 0.004. There was statistically significant difference between the treatment group in the occurrence of inflammatory root resorption (P = 0.015 and the occurrence of replacement root resorption (P = 0.041. Conclusions: Emdogain gel used on the surface of transplanted teeth improves the occurrence of complete healing and reduces root resorption.

  4. Cephalic Arch Stenosis in Autogenous Haemodialysis Fistulas: Treatment With the Viabahn Stent-Graft

    Energy Technology Data Exchange (ETDEWEB)

    Shawyer, Andrew, E-mail: andrew.shawyer@bartsandthelondon.nhs.uk [The Royal London Hospital, Radiology Department (United Kingdom); Fotiadis, Nicos I., E-mail: fotiadis.nicholas@gmail.com [Royal Marsden Hospital, Radiology Department, The Royal Marsden NHS Foundation Trust (United Kingdom); Namagondlu, Girish, E-mail: girish.namagondlu@bartsandthelondon.nhs.uk [The Royal London Hospital, Renal Medicine Department (United Kingdom); Iyer, Arun, E-mail: arun.iyer@bartsandthelondon.nhs.uk [The Royal London Hospital, Radiology Department (United Kingdom); Blunden, Mark, E-mail: mark.blunden@bartsandthelondon.nhs.uk; Raftery, Martin, E-mail: martin.raftery@bartsandthelondon.nhs.uk; Yaqoob, Magdi, E-mail: magdi.yaqoob@bartsandthelondon.nhs.uk [The Royal London Hospital, Renal Medicine Department (United Kingdom)

    2013-02-15

    Cephalic arch stenosis (CAS) is an important and common cause of dysfunction in autogenous haemodialysis fistulas that requires multiple reinterventions and aggressive surveillance. We evaluated the safety and efficacy of the Viabahn stent-graft for the management of CAS. Between April 2005 and October 2011, 11 consecutive patients [four men and seven women (mean age 56.7 years)] with CAS and dysfunctional fistulas were treated with insertion of 11 Viabahn stent-grafts. Six stent-grafts were inserted due to residual stenosis after angioplasty and five for fistuloplasty-induced rupture. No patient was lost to follow-up. The technical and clinical success rate was 100 %. Primary access patency rates were 81.8 % [95 % confidence interval (CI) 0.482-0.977] at 6 months and 72.7 % (95 % CI 0.390-0.939) at 12 months. Secondary access patency rates were 90.9 % at 6 months (95 % CI 0.587-0.997). There were no procedure-related complications. Mean follow-up was 543.8 days (range 156-2,282). The use of the Viabahn stent-graft in the management of CAS is technically feasible and, in this small series, showed patency rates that compare favorably with historical data of angioplasty and bare stents.

  5. Effect of percutaneous transluminal angioplasty on the stenosis of autogenous radiocephalic ateriovenous fistula for hemodialysis

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Sun Min; Kim, Jeong Ho; Byun, Sung Su; Kang, Jin MMo; Choi, Sang Tae; Kim, Jong Woo; Kim, Hyung Sik; Choi, Hye Young [Gachon University Gil Medical Center, Incheon (Korea, Republic of); Park, Jae Hyung [Dept. of Radiology, Seonam University College of Medicine, Myongji Hospital, Goyang (Korea, Republic of)

    2016-02-15

    The purpose of this study was to evaluate the effectiveness of percutaneous transluminal angioplasty (PTA) on stenosis of autogenous radiocephalic arteriovenous fistula (RCF) for hemodialysis and to determine the factors influencing patency. This retrospective study included 136 patients referred for PTA of RCF stenosis between March 2005 and July 2014. The technical success rate, complications, and patency rate were evaluated. The following factors were analyzed as they might influence patency: age, gender, site and duration of arteriovenous fistula, underlying disease, body mass index, hypercholesterolemia, smoking, peripheral artery or coronary artery occlusive disease, stenosis length/grade, cutting balloon, and balloon size. The initial technical success rate was 91.9% (125/136). Complications included vessel rupture (n = 2) and vessel dissection (n = 2). The patency rates at 6, 12, 24, and 48 months after PTA were 81.9, 67.1, 52.7, and 42.3%, respectively. The patency rate was higher in cases with longer (> 3 cm) stenosis (p = 0.04). Use of cutting balloon and larger size of balloon catheter made the patency longer, but this difference was not statistically significant (p = 0.637, 0.258). PTA is a safe and effective way to manage stenosis in RCF. The length of stenosis was the only factor which affected the patency rate in this study.

  6. Silicate minerals for CO2 scavenging from biogas in Autogenerative High Pressure Digestion.

    Science.gov (United States)

    Lindeboom, Ralph E F; Ferrer, Ivet; Weijma, Jan; van Lier, Jules B

    2013-07-01

    Autogenerative High Pressure Digestion (AHPD) is a novel concept that integrates gas upgrading with anaerobic digestion by selective dissolution of CO2 at elevated biogas pressure. However, accumulation of CO2 and fatty acids after anaerobic digestion of glucose resulted in pH 3-5, which is incompatible with the commonly applied high-rate methanogenic processes. Therefore, we studied the use of wollastonite, olivine and anorthosite, with measured composition of CaSi1.05O3.4, Mg2Fe0.2Ni0.01Si1.2O5.3 and Na0.7Ca1K0.1Mg0.1Fe0.15Al3.1Si4O24, respectively, to scavenge CO2 during batch AHPD of glucose. Depending on the glucose to mineral ratio the pH increased to 6.0-7.5. Experiments with wollastonite showed that Ca(2+)-leaching was caused by volatile fatty acid (VFA) production during glucose digestion. At 1, 3 and 9 bar, the CH4 content reached 74%, 86% and 88%, respectively, indicating CO2 scavenging. Fixation of produced CO2 by CaCO3 precipitation in the sludge was confirmed by Fourier Transferred-InfraRed, Combined Field emission Scanning Electron Microscopy-Energy-dispersive X-ray spectroscopy and Thermogravimetric Analysis-Mass Spectroscopy.

  7. High-performance binders with reduced autogenous shrinkage on the basis of fine cement

    Energy Technology Data Exchange (ETDEWEB)

    Martschuk, V. [Inst. of the Cement Industry, Dusseldorf (Germany)

    2001-07-01

    A study on the hydration of portland cement was presented. The paper presented special features of the chemical shrinkage of cement paste at high and low water-cement ratios. It also described the effect of silica fume on the deformation behaviour of cement paste, as well as on the behaviour of hardened binder paste at water-binder ratios of 0.40 and 0.25. High performance concrete has a high density and a tendency to chemically shrink because of its low water-cement ratio. The study showed that the autogenous shrinkage increases if silica fume is added. Theoretical calculations were performed and showed that the typical addition of silica fume results in an increase in total porosity, and therefore, to the deterioration of the packing density of the binder mixture. The specific surface area of the dry powder is also increased. It was concluded that replacing cement by optimized fine cements improves the theoretical packing density in binders. The hardened cement paste studies showed that this makes a cement that is denser with less tendency to shrink. 7 refs., 3 tabs., 8 figs.

  8. Autogenic-Feedback Training: A Potential Treatment for Orthostatic Intolerance in Aerospace Crews

    Science.gov (United States)

    Cowings, P. S.; Toscano, W. B.; Miller, N. E.; Pickering, T. G.; Shapiro, D.; Stevenson, J.; Maloney, S.; Knapp, J.

    1994-01-01

    Postflight orthostatic intolerance has been identified as a serious biomedical problem associated with long-duration exposure to microgravity in space. High priority has been given to the development of countermeasures for this disorder that are both effective and practical. A considerable body of clinical research has demonstrated that people can be taught to increase their own blood pressure voluntarily, and that this is an effective treatment for chronic orthostatic intolerance in paralyzed patients. The current pilot study was designed to examine the feasibility of adding training in control of blood pressure to an existing preflight training program designed to facilitate astronaut adaptation to microgravity. Using an operant conditioning procedure, autogenic-feedback training (AFT), three men and two women participated in four to nine training (15-30-minute) sessions. At the end of training, the average increase in systolic and diastolic pressure, as well as mean arterial pressures, that the subjects made ranged between 20 and 50 mm Hg under both supine and 45 deg head-up tilt conditions. These findings indicate that AFT may be a useful alternative treatment or supplement to existing approaches for preventing postflight orthostatic intolerance. Furthermore, the use of operant conditioning methods for training cardiovascular responses may contribute to the general understanding of the mechanisms of orthostatic intolerance.

  9. Autogenic-feedback training: A potential treatment for post-flight orthostatic intolerance in aerospace crews

    Science.gov (United States)

    Cowings, Patricia S.; Toscano, William B.; Miller, Neil E.; Pickering, Thomas G.; Shapiro, David

    1993-01-01

    Postflight orthostatic intolerance was identified as a serious biomedical problem associated with long duration exposure to microgravity in space. High priority was given to the development of countermeasures for this disorder which are both effective and practical. A considerable body of clinical research demonstrated that people can be taught to increase their own blood pressure voluntarily and that this is an effective treatment for chronic orthostatic intolerance in paralyzed patients. The present pilot study was designed to examine the feasibility of adding training in control of blood pressure to an existing preflight training program designed to facilitate astronaut adaptation to microgravity. Using an operant conditioning procedure, Autogenic-Feedback Training (AFT), three men and two women participated in four to nine (15-30 training sessions). At the end of training, the average increase in systolic and diastolic pressure, as well as mean arterial pressures that the subjects made, ranged between 20 and 5O mmHg under both supine and 45 deg head-up tilt conditions. These findings suggest that AFT may be a useful alternative treatment or supplement to existing approaches for preventing postflight orthostatic intolerance. Further, the use of operant conditioning methods for training cardiovascular responses may contribute to the general understanding of the mechanisms of orthostatic intolerance.

  10. A Novel Albumin-Based Tissue Scaffold for Autogenic Tissue Engineering Applications

    Science.gov (United States)

    Li, Pei-Shan; -Liang Lee, I.; Yu, Wei-Lin; Sun, Jui-Sheng; Jane, Wann-Neng; Shen, Hsin-Hsin

    2014-07-01

    Tissue scaffolds provide a framework for living tissue regeneration. However, traditional tissue scaffolds are exogenous, composed of metals, ceramics, polymers, and animal tissues, and have a defined biocompatibility and application. This study presents a new method for obtaining a tissue scaffold from blood albumin, the major protein in mammalian blood. Human, bovine, and porcine albumin was polymerised into albumin polymers by microbial transglutaminase and was then cast by freeze-drying-based moulding to form albumin tissue scaffolds. Scanning electron microscopy and material testing analyses revealed that the albumin tissue scaffold possesses an extremely porous structure, moderate mechanical strength, and resilience. Using a culture of human mesenchymal stem cells (MSCs) as a model, we showed that MSCs can be seeded and grown in the albumin tissue scaffold. Furthermore, the albumin tissue scaffold can support the long-term osteogenic differentiation of MSCs. These results show that the albumin tissue scaffold exhibits favourable material properties and good compatibility with cells. We propose that this novel tissue scaffold can satisfy essential needs in tissue engineering as a general-purpose substrate. The use of this scaffold could lead to the development of new methods of artificial fabrication of autogenic tissue substitutes.

  11. Bone regeneration by octacalcium phosphate collagen composites in a dog alveolar cleft model.

    Science.gov (United States)

    Matsui, K; Matsui, A; Handa, T; Kawai, T; Suzuki, O; Kamakura, S; Echigo, S

    2010-12-01

    Octacalcium phosphate (OCP) and porcine atelocollagen sponge composites (OCP/Col) markedly enhanced bone regeneration in a rat cranial defect model. To assess clinical application, the authors examined whether OCP/Col would enhance bone regeneration in an alveolar cleft model in an adult dog, which was assumed to reflect patients with alveolar cleft. Disks of OCP/Col or collagen were implanted into the defect and bone regeneration by OCP/Col or collagen was investigated 4 months after implantation. Macroscopically, the OCP/Col-treated alveolus was obviously augmented and occupied by radio-opacity, and the border between the original bone and the defect was indistinguishable. Histological analysis revealed it was filled and bridged with newly formed bone; a small quantity of the remaining implanted OCP was observed. X-ray diffraction patterns of the area of implanted OCP/Col indicated no difference from those of dog bone. In the collagen-treated alveolus, the hollowed alveolus was mainly filled with fibrous connective tissue, and a small amount of new bone was observed at the defect margin. These results suggest that bone was obviously repaired when OCP/Col was implanted into the alveolar cleft model in a dog, and OCP/Col would be a significant bone regenerative material to substitute for autogeneous bone.

  12. Repair of segmental bone defects with bone marrow and BMP-2 adenovirus in the rabbit radius

    Science.gov (United States)

    Cheng, Lijia; Lu, Xiaofeng; Shi, Yujun; Li, Li; Xue, Jing; Zhang, Li; Xia, Jie; Wang, Yujia; Zhang, Xingdong; Bu, Hong

    2012-12-01

    Bone tissue engineering (BTE) is approached via implantation of autogenous mesenchymal stem cells (MSCs), marrow cells, or platelet-rich plasma, etc. To the contrary, gene therapy combining with the bone marrow (BM) has not been often reported. This study was performed to investigate whether a modified BTE method, that is, the BM and a recombinant human bone morphogenetic protein-2 adenovirus (Ad.hBMP-2) gene administering in hydroxyapatite/β-tricalcium phosphate (HA/β-TCP) ceramics could accelerate the healing of segmental defects in the rabbit radius. In our study, ceramics were immersed in the adenovirus overnight, and half an hour before surgery, autologous BM aspirates were thoroughly mixed with the ceramics; at the same time, a 15-mm radius defect was introduced in the bilateral forelimbs of all animals, after that, this defect was filled with the following: (1) Ad.hBMP-2 + HA/β-TCP + autologous BM (group 1); (2) HA/β-TCP + Ad.hBMP-2 (group 2); (3) HA/β-TCP alone (group 3); (4) an empty defect as a control (group 4). Histological observation and μ-CT analyses were performed on the specimens at weeks 2, 4, 8, and 12, respectively. In group 1, new bone was observed at week 4 and BM appeared at week 12, in groups 2 and 3, new bone was observed at week 8 and it was more mature at week 12, in contrast, the defect was not bridged in group 4 at week 12. The new bone area percentage in group 1 was significantly higher than that in groups 2 and 3. Our study indicated that BM combined with hBMP-2 adenovirus and porous ceramics could significantly increase the amount of newly formed bone. And this modified BTE method thus might have potentials in future clinical application.

  13. Oblique dust density waves

    Science.gov (United States)

    Piel, Alexander; Arp, Oliver; Menzel, Kristoffer; Klindworth, Markus

    2007-11-01

    We report on experimental observations of dust density waves in a complex (dusty) plasma under microgravity. The plasma is produced in a radio-frequency parallel-plate discharge (argon, p=15Pa, U=65Vpp). Different sizes of dust particles were used (3.4 μm and 6.4μm diameter). The low-frequency (f 11Hz) dust density waves are naturally unstable modes, which are driven by the ion flow in the plasma. Surprisingly, the wave propagation direction is aligned with the ion flow direction in the bulk plasma but becomes oblique at the boundary of the dust cloud with an inclination of 60^o with respect to the plasma boundary. The experimental results are compared with a kinetic model in the electrostatic approximation [1] and a fluid model [2]. Moreover, the role of dust surface waves is discussed. [1] M. Rosenberg, J. Vac. Sci. Technol. A 14, 631 (1996) [2] A. Piel et al, Phys. Rev. Lett. 97, 205009 (2006)

  14. Planar dust-acoustic waves in electron-positron-ion-dust plasmas with dust size distribution

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hong-Yan; Zhang, Kai-Biao [Sichuan University of Science and Engineering, Zigong (China)

    2014-06-15

    Nonlinear dust-acoustic solitary waves which are described with a Kortweg-de vries (KdV) equation by using the reductive perturbation method, are investigated in a planar unmagnetized dusty plasma consisting of electrons, positrons, ions and negatively-charged dust particles of different sizes and masses. The effects of the power-law distribution of dust and other plasma parameters on the dust-acoustic solitary waves are studied. Numerical results show that the dust size distribution has a significant influence on the propagation properties of dust-acoustic solitons. The amplitudes of solitary waves in the case of a power-law distribution is observed to be smaller, but the soliton velocity and width are observed to be larger, than those of mono-sized dust grains with an average dust size. Our results indicate that only compressed solitary waves exist in dusty plasma with different dust species. The relevance of the present investigation to interstellar clouds is discussed.

  15. Differential performance on the go/no-go task as a function of the autogenous-reactive taxonomy of obsessions: findings from a non-treatment seeking sample.

    Science.gov (United States)

    Lee, Han-Joo; Yost, Brittanie P; Telch, Michael J

    2009-04-01

    It has been suggested that obsessive-compulsive disorder is characterized by impaired inhibitory control. Response inhibition is a cognitive process required for one to cancel or suppress dominant but inappropriate responses. The present study examined response inhibition among non-treatment seeking individuals diagnosed with OCD and individuals with low levels of OCD symptoms using a computerized visual go/no-go task. Specifically, we sought to examine a prediction from the autogenous-reactive subtype model of obsessions (Lee, H.-J., & Kwon, S.-M. (2003). Two different types of obsession: autogenous obsessions and reactive obsessions. Behaviour Research and Therapy, 41, 11-29; Lee, H.-J., & Telch, M. J. (2008). Autogenous obsessions and reactive obsessions. In J. Abramowitz, S. Taylor, & D. McKay (Eds.), Obsessive-compulsive disorder: subtypes and spectrum conditions. New York: Elsevier., asserting that OCD individuals presenting with the autogenous subtype of obsessions will display greater difficulty in inhibitory control relative to individuals presenting with obsessions of the reactive subtype. Results showed that individuals with OCD of the autogenous subtype displayed more deficient inhibitory control on the visual go/no-go task as indexed by a longer response delay between the original stimuli set and the reversed stimuli set compared to individuals with OCD of the reactive subtype or individuals with low levels of OCD symptoms.

  16. Osteogenesis effect of guided bone regeneration combined with alveolar cleft grafting: assessment by cone beam computed tomography.

    Science.gov (United States)

    Xiao, W-L; Zhang, D-Z; Chen, X-J; Yuan, C; Xue, L-F

    2016-06-01

    Cone beam computed tomography (CBCT) allows for a significantly lower radiation dose than conventional computed tomography (CT) scans and provides accurate images of the alveolar cleft area. The osteogenic effect of guided bone regeneration (GBR) vs. conventional alveolar bone grafting alone for alveolar cleft defects was evaluated in this study. Sixty alveolar cleft patients were divided randomly into two groups. One group underwent GBR using acellular dermal matrix film combined with alveolar bone grafting using iliac crest bone grafts (GBR group), while the other group underwent alveolar bone grafting only (non-GBR group). CBCT images were obtained at 1 week and at 3 months following the procedure. Using Simplant 11.04 software, the bone resorption rate was calculated and compared between the two groups. The bone resorption rate from 1 week to 3 months following bone grafting without the GBR technique was 36.50±5.04%, whereas the bone resorption rate using the GBR technique was 31.69±5.50% (P=0.017). The application of autogenous iliac bone combined with the GBR technique for alveolar bone grafting of alveolar cleft patients can reduce bone resorption and result in better osteogenesis.

  17. Dust exposure in Finnish foundries.

    Science.gov (United States)

    Siltanen, E; Koponen, M; Kokko, A; Engström, B; Reponen, J

    1976-01-01

    Dust measurements were made in 51 iron, 9 steel, and 8 nonferrous foundries, at which 4,316 foundrymen were working. The sampling lasted at least two entire shifts or work days continuously during various operations in each foundry. The dust samples were collected at fixed sites or in the breathing zones of the workers. The mass concentration was determined by weighing and the respirable dust fraction was separated by liquid sedimentation. The free silica content was determined by X-ray diffraction. In the study a total of 3,188 samples were collected in the foundries and 6,505 determinations were made in the laboratory. The results indicated a definite difference in the dust exposure during various operations. The highest dust exposures were found during furnace, cupola, and pouring ladle repair. During cleaning work, sand mixing, and shake-out operations excessive silica dust concentrations were also measured. The lowest dust concentrations were measured during melting and pouring operations. Moderate dust concentrations were measured during coremaking and molding operations. The results obtained during the same operations of iron and steel foundries were similar. The distribution of the workers into various exposure categories, the content of respirable dust and quartz, the correlation between respirable dust and total dust, and the correlation between respirable silica and total dust concentrations are discussed. Observations concerning dust suppression and control methods are briefly considered.

  18. Effect of morselized bones on binding of the canine hydroxyapatite-coated femoral stem

    Institute of Scientific and Technical Information of China (English)

    SONG Ke-guan; MA De-sheng; HOU Jian-wen; WANG Huan; YAN Jing-long; YU Zhan-ge; LIANG Zhi-zhong

    2010-01-01

    Background Non-cement femoral stems are recognized in clinical use, but there are still some problems. The aim of this research was to make non-cement femoral stems to be press-fit with the medullary cavity. Methods Twenty-four healthy adult mongrel dogs were randomly divided into experimental and control groups. In the right hip joint, an artificial femoral bone replacement surgery was conducted. For the experimental group, the replacement surgery of hydroxyapatite (HA)-coated femoral stems was done, while autogeneous morselized bone was implanted into the medullary cavity. For the control group, morselized bone was not implanted. At postoperative 1, 3, 6 months, a test for interfacial shear characteristics was conducted in the MTS810 Tester. The comparison between the two groups' bone-prostheses in shear strength for their interface from shearing destruction was made. A histological observation to check prosthesis-bone interface contact ratios and bone growth was carried out. Results For the experimental group, shear strength was 0.317 MPa in 1 month, 1.447 MPa in 3 months, and 1.621 MPa in 6 months. For the control group, shear strength was 0.195 MPa in 1 month, 1.023 MPa in 3 months, and 1.483 MPa in 6 months. The difference was statistically significant. Stereomicroscope-based observation showed that the number of trabecular bones in the experimental group was larger than that of the control group, and bone growth of the former group was better than that of the latter group. Inverted microscopic observation showed that the binding degree between the prosthesis and trabecular bone of the experimental group was higher than that of the control group. Comparatively, the experimental group's trabecular bone had more stromal cells. Conclusions The morselized bones can effectively improve the biological bonding strength and bone-contact ratios in the short term for the HA-coated femoral stem and accelerate the bonding process. The use of morselized autogenous bones

  19. Analytical Study of Nonlinear Dust Acoustic Waves in Two-Dimensional Dust Plasma with Dust Charge Variation

    Institute of Scientific and Technical Information of China (English)

    LIN Chang; ZHANG Xiu-Lian

    2005-01-01

    The nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation is analytically investigated by using the formally variable separation approach. New analytical solutions for the governing equation of this system have been obtained for dust acoustic waves in a dust plasma for the first time. We derive exact analytical expressions for the general case of the nonlinear dust acoustic waves in two-dimensional dust plasma with dust charge variation.

  20. Dust Devil Tracks

    Science.gov (United States)

    Reiss, Dennis; Fenton, Lori; Neakrase, Lynn; Zimmerman, Michael; Statella, Thiago; Whelley, Patrick; Rossi, Angelo Pio; Balme, Matthew

    2016-11-01

    Dust devils that leave dark- or light-toned tracks are common on Mars and they can also be found on the Earth's surface. Dust devil tracks (hereinafter DDTs) are ephemeral surface features with mostly sub-annual lifetimes. Regarding their size, DDT widths can range between ˜1 m and ˜1 km, depending on the diameter of dust devil that created the track, and DDT lengths range from a few tens of meters to several kilometers, limited by the duration and horizontal ground speed of dust devils. DDTs can be classified into three main types based on their morphology and albedo in contrast to their surroundings; all are found on both planets: (a) dark continuous DDTs, (b) dark cycloidal DDTs, and (c) bright DDTs. Dark continuous DDTs are the most common type on Mars. They are characterized by their relatively homogenous and continuous low albedo surface tracks. Based on terrestrial and martian in situ studies, these DDTs most likely form when surficial dust layers are removed to expose larger-grained substrate material (coarse sands of ≥500 μm in diameter). The exposure of larger-grained materials changes the photometric properties of the surface; hence leading to lower albedo tracks because grain size is photometrically inversely proportional to the surface reflectance. However, although not observed so far, compositional differences (i.e., color differences) might also lead to albedo contrasts when dust is removed to expose substrate materials with mineralogical differences. For dark continuous DDTs, albedo drop measurements are around 2.5 % in the wavelength range of 550-850 nm on Mars and around 0.5 % in the wavelength range from 300-1100 nm on Earth. The removal of an equivalent layer thickness around 1 μm is sufficient for the formation of visible dark continuous DDTs on Mars and Earth. The next type of DDTs, dark cycloidal DDTs, are characterized by their low albedo pattern of overlapping scallops. Terrestrial in situ studies imply that they are formed when sand

  1. Dust during the Reionization

    CERN Document Server

    Elfgren, E; Elfgren, Erik

    2003-01-01

    The possibility that population III stars have reionized the Universe at redshifts greater than 6 has recently gained momentum with WMAP polarization results. Here we analyse the role of early dust produced by these stars and ejected into the intergalactic medium. We show that this dust, heated by the radiation from the same population III stars, produces a submillimetre excess. The electromagnetic spectrum of this excess is compatible with the FIRAS (Far Infrared Absolute Spectrophotometer) cosmic far infrared background. This spectrum, a Doppler spectrum times the $\

  2. Dust Devil Days

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Released 6 July 2004 The atmosphere of Mars is a dynamic system. Water-ice clouds, fog, and hazes can make imaging the surface from space difficult. Dust storms can grow from local disturbances to global sizes, through which imaging is impossible. Seasonal temperature changes are the usual drivers in cloud and dust storm development and growth. Eons of atmospheric dust storm activity has left its mark on the surface of Mars. Dust carried aloft by the wind has settled out on every available surface; sand dunes have been created and moved by centuries of wind; and the effect of continual sand-blasting has modified many regions of Mars, creating yardangs and other unusual surface forms. Dust devils, small cyclonic wind storms, are common in the American Southwest and on Mars. As the dust devil moves across the surface it picks up the loose dust, leaving behind a dark track to mark its passage. These dust devil tracks are in the Argyre Basin. Image information: VIS instrument. Latitude -46.6, Longitude 317.5 East (42.5 West). 19 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the

  3. Electrostatic Characterization of Lunar Dust

    Science.gov (United States)

    2008-01-01

    To ensure the safety and success of future lunar exploration missions, it is important to measure the toxicity of the lunar dust and its electrostatic properties. The electrostatic properties of lunar dust govern its behavior, from how the dust is deposited in an astronaut s lungs to how it contaminates equipment surfaces. NASA has identified the threat caused by lunar dust as one of the top two problems that need to be solved before returning to the Moon. To understand the electrostatic nature of lunar dust, NASA must answer the following questions: (1) how much charge can accumulate on the dust? (2) how long will the charge remain? and (3) can the dust be removed? These questions can be answered by measuring the electrostatic properties of the dust: its volume resistivity, charge decay, charge-to-mass ratio or chargeability, and dielectric properties.

  4. Evaluation of the osteogenesis and angiogenesis effects of erythropoietin and the efficacy of deproteinized bovine bone/recombinant human erythropoietin scaffold on bone defect repair.

    Science.gov (United States)

    Li, Donghai; Deng, Liqing; Xie, Xiaowei; Yang, Zhouyuan; Kang, Pengde

    2016-06-01

    Erythropoietin (EPO) could promote the angiogenesis and may also play a role in bone regeneration. This study was conducted to evaluate the osteogenesis and angiogenesis effects of EPO and the efficacy of deproteinized bovine bone/recombinant human EPO scaffold on bone defect repair. Twenty-four healthy adult goats were chosen to build goat defects model and randomly divided into four groups. The goats were treated with DBB/rhEPO scaffolds (group A), porous DBB scaffolds (group B), autogenous cancellous bone graft (group C), and nothing (group D). Animals were evaluated with radiological and histological methods at 4, 8 and 12 weeks after surgery. The grey value of radiographs was used to evaluate the healing of the defects and the outcome revealed that the group A had a better outcome of defect healing compared with group B (P 0.05). The newly formed bone area was calculated from histological sections and the results demonstrated that the amount of new bone in group A increased significantly compared with that in group B (P 0.05) at 4, 8, 12 weeks respectively. In addition, the expression of vascular endothelial growth factor (VEGF) by immunohistochemical testing and real-time polymerase chain reaction at 12 weeks in group A was significantly higher than that in group B (P 0.05). Therefore, EPO has significant effects on bone formation and angiogenesis, and has capacity to promote the repair of bone defects. It is worthy of being recommended to further studies.

  5. Heterotopic bone formation in the musculus latissimus dorsi of sheep using β-tricalcium phosphate scaffolds: evaluation of an extended prefabrication time on bone formation and matrix degeneration.

    Science.gov (United States)

    Spalthoff, S; Jehn, P; Zimmerer, R; Möllmann, U; Gellrich, N-C; Kokemueller, H

    2015-06-01

    We previously generated viable heterotopic bone in living animals and found that 3 months of intrinsic vascularization improved bone formation and matrix degeneration. In this study, we varied the pre-vascularization time to determine its effects on the kinetics of bone formation and ceramic degradation. Two 25-mm-long cylindrical β-tricalcium phosphate scaffolds were filled intraoperatively with autogenous iliac crest bone marrow and implanted in the latissimus dorsi muscle in six sheep. To examine the effect of axial perfusion, one scaffold was surgically implanted with (group C) or without (group D) a central vascular bundle. All animals were sacrificed 6 months postoperatively and histomorphometric measurements were compared to previous results. All implanted scaffolds exhibited ectopic bone growth. However, bone growth was not significantly different between the 3-month (group A, 0.191±0.097 vs. group C, 0.237±0.075; P=0.345) and 6-month (group B, 0.303±0.105 vs. group D, 0.365±0.258; P=0.549) pre-vascularization durations, regardless of vessel supply; early differences between surgically and extrinsically vascularized constructs disappeared after 6 months. Here, we describe a reliable procedure for generating ectopic bone in vivo. A 3-month pre-vascularization duration appears sufficient and ceramic degradation proceeds in accordance with bone generation, supporting the hypothesis of cell-mediated resorption.

  6. Effect of bone block removal and patellar prosthesis on stresses in the human patella.

    Science.gov (United States)

    Friis, E A; Cooke, F W; McQueen, D A; Henning, C E

    1994-01-01

    Thermoelastic stress analysis was used to examine stresses on the anterior surface of patellae after patellar bone block excision for autogenous graft anterior cruciate ligament reconstruction. Complications of anterior cruciate ligament injury often lead to degenerative changes in the knee that can require total knee joint replacement. It was hypothesized that stresses in a bone block-compromised patella may be increased even further by insertion of a patellar prosthesis. All patellae were first tested intact and then were retested after a sequence of surgical modifications including patellar prosthesis implantation, tapered bone block excision, square bone block excision, and both shapes of excised bone blocks with a patellar prosthesis in place. Stresses in patellae with bone blocks excised were significantly greater than stresses in intact patellae. The anterior surface stress pattern in the loaded patella was significantly altered by excision of a bone block. There were no significant differences between maximum stress in patellae with tapered and square bone blocks excised. A finite element analysis showed that excision of a larger trapezoid-shaped bone block greatly increased maximum stress levels. Insertion of a patellar prosthesis did not significantly alter stress patterns or maximum stress levels in the patella.

  7. Application of platelet-rich plasma with stem cells in bone and periodontal tissue engineering

    Science.gov (United States)

    Fernandes, Gabriela; Yang, Shuying

    2016-01-01

    Presently, there is a high paucity of bone grafts in the United States and worldwide. Regenerating bone is of prime concern due to the current demand of bone grafts and the increasing number of diseases causing bone loss. Autogenous bone is the present gold standard of bone regeneration. However, disadvantages like donor site morbidity and its decreased availability limit its use. Even allografts and synthetic grafting materials have their own limitations. As certain specific stem cells can be directed to differentiate into an osteoblastic lineage in the presence of growth factors (GFs), it makes stem cells the ideal agents for bone regeneration. Furthermore, platelet-rich plasma (PRP), which can be easily isolated from whole blood, is often used for bone regeneration, wound healing and bone defect repair. When stem cells are combined with PRP in the presence of GFs, they are able to promote osteogenesis. This review provides in-depth knowledge regarding the use of stem cells and PRP in vitro, in vivo and their application in clinical studies in the future. PMID:28018706

  8. BMP2-loaded hollow hydroxyapatite microspheres exhibit enhanced osteoinduction and osteogenicity in large bone defects.

    Science.gov (United States)

    Xiong, Long; Zeng, Jianhua; Yao, Aihua; Tu, Qiquan; Li, Jingtang; Yan, Liang; Tang, Zhiming

    2015-01-01

    The regeneration of large bone defects is an osteoinductive, osteoconductive, and osteogenic process that often requires a bone graft for support. Limitations associated with naturally autogenic or allogenic bone grafts have demonstrated the need for synthetic substitutes. The present study investigates the feasibility of using novel hollow hydroxyapatite microspheres as an osteoconductive matrix and a carrier for controlled local delivery of bone morphogenetic protein 2 (BMP2), a potent osteogenic inducer of bone regeneration. Hollow hydroxyapatite microspheres (100±25 μm) with a core (60±18 μm) and a mesoporous shell (180±42 m(2)/g surface area) were prepared by a glass conversion technique and loaded with recombinant human BMP2 (1 μg/mg). There was a gentle burst release of BMP2 from microspheres into the surrounding phosphate-buffered saline in vitro within the initial 48 hours, and continued at a low rate for over 40 days. In comparison with hollow hydroxyapatite microspheres without BMP2 or soluble BMP2 without a carrier, BMP2-loaded hollow hydroxyapatite microspheres had a significantly enhanced capacity to reconstitute radial bone defects in rabbit, as shown by increased serum alkaline phosphatase; quick and complete new bone formation within 12 weeks; and great biomechanical flexural strength. These results indicate that BMP2-loaded hollow hydroxyapatite microspheres could be a potential new option for bone graft substitutes in bone regeneration.

  9. Identification of the exploatation dust in road dust

    Directory of Open Access Journals (Sweden)

    B. Gajdzik

    2012-01-01

    Full Text Available The aim of this publication is to determine models of explore dust from vehicle brake systems and the presentationof measurement results of the exploitation dust, which is separate from road dust. The following methods and measuring devices were used: T-01M device, screen analysis, analysis of chemical composition with the use of a scanning microscope with Energy Dispersive x-ray Spectroscopy (EDS analyser. The measurements for identifying this type of dust were conducted on marked sections of roads: motorway, city road and mountain road. The explored dust was distinguished in the following car systems: brakes, clutch plates, tyres and catalytic converters.

  10. 腹式呼吸和自生训练对心率及指温影响的初步探讨%The Effects of Abdominal Breathing and Autogenic Training on Heart Rate and Finger Temperature

    Institute of Scientific and Technical Information of China (English)

    张秀阁; 闫克乐

    2001-01-01

    Objective: To examine the effects of autogenic training and abdominal breathing on heart rate and finger temperature. Methods: Forty-five healthy female university students were randomly assigned to three groups:control、autogenic training and deep abdominal breathing groups, and their physiological effects were compared. Results:The result of this experiment showed that both autogenic training and abdominal breathing increased finger temperature significantly, however, the increase magnitude didn't show significant differences in two groups.During autogenic training, the heart rate of autogenic training group declined significantly,the heart rate of deep abdominal breathing group decreased significantly after deep abdominal breathing. The decrease magnitude between the three groups showed no significant differences. Conclusion: Both the present techniques can decrease heart rate and increase finger temperature.

  11. [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

  12. Self-organization in irregular landscapes: Detecting autogenic interactions from field data using descriptive statistics and dynamical systems theory

    Science.gov (United States)

    Larsen, L.; Watts, D.; Khurana, A.; Anderson, J. L.; Xu, C.; Merritts, D. J.

    2015-12-01

    The classic signal of self-organization in nature is pattern formation. However, the interactions and feedbacks that organize depositional landscapes do not always result in regular or fractal patterns. How might we detect their existence and effects in these "irregular" landscapes? Emergent landscapes such as newly forming deltaic marshes or some restoration sites provide opportunities to study the autogenic processes that organize landscapes and their physical signatures. Here we describe a quest to understand autogenic vs. allogenic controls on landscape evolution in Big Spring Run, PA, a landscape undergoing restoration from bare-soil conditions to a target wet meadow landscape. The contemporary motivation for asking questions about autogenic vs. allogenic controls is to evaluate how important initial conditions or environmental controls may be for the attainment of management objectives. However, these questions can also inform interpretation of the sedimentary record by enabling researchers to separate signals that may have arisen through self-organization processes from those resulting from environmental perturbations. Over three years at Big Spring Run, we mapped the dynamic evolution of floodplain vegetation communities and distributions of abiotic variables and topography. We used principal component analysis and transition probability analysis to detect associative interactions between vegetation and geomorphic variables and convergent cross-mapping on lidar data to detect causal interactions between biomass and topography. Exploratory statistics revealed that plant communities with distinct morphologies exerted control on landscape evolution through stress divergence (i.e., channel initiation) and promoting the accumulation of fine sediment in channels. Together, these communities participated in a negative feedback that maintains low energy and multiple channels. Because of the spatially explicit nature of this feedback, causal interactions could not

  13. NASA-Navy Telemedicine: Autogenic Feedback Training Exercises for Motion Sickness

    Science.gov (United States)

    Acromite, Michael T.; Cowings, Patricia; Toscano, William; Davis, Carl; Porter, Henry O.

    2010-01-01

    Airsickness is the most significant medical condition affecting naval aviation training. A 2001 study showed that airsickness was reported in 81% of naval aviation students and was associated with 82% of below average flight scores. The cost to a single training air-wing was over $150,000 annually for fuel and maintenance costs alone. Resistent cases are sent to the Naval Aerospace Medical Institute (NAMI) for evaluation and desensitization in the self-paced airsickness desensitization (SPAD) program. This approach is 75% successful, but can take up to 8 weeks at a significant travel cost. NASA Ames Research Center's Autogenic Feedback Training Exercises (AFTE) uses physiological and biofeedback training for motion sickness prevention. It has a remote capability that has been used from Moffett Field, CA to Atlanta, GA . AFTE is administered in twelve (30-minute) training sessions. The success rate for the NASA AFTE program has been over 85%. Methods: Implementation Phases: Phase I: Transfer NASA AFTE to NAMI; NASA will remotely train aviation students at NAMI. Phase II: NAMI-centered AFTE application with NASA oversight. Phase III: NAMI-centered AFTE to remotely train at various Navy sites. Phase IV: NAMI to offer Tri-service application and examine research opportunities. Results: 1. Use available telemedicine connectivity between NAMI and NASA. 2. Save over $2,000 per student trained. 3. Reduce aviation training attrition. 4. Provide standardization of multi-location motion sickness training. 5. Future tri-service initiatives. 6. Data to NASA and Navy for QA and research opportunities.

  14. Clinical trial comparing autogenous fascia lata sling and Gore-Tex suspension in bilateral congenital ptosis

    Directory of Open Access Journals (Sweden)

    Elsamkary MA

    2016-03-01

    Full Text Available Mahmoud Ahmed Elsamkary,1 Maged Maher Salib Roshdy1,2 1Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt; 2Pediatric Ophthalmology Department, Al Watany Eye Hospital, Cairo, Egypt Purpose: To study the effect of autogenous fascia lata sling (AFLS versus Gore-Tex suspension (GTS regarding the functional and aesthetic outcomes in patients with bilateral congenital ptosis. Patients and methods: A prospective comparative randomized single-center study enrolled 110 patients with bilateral congenital ptosis. One group (n=55 underwent AFLS and the second group (n=55 underwent GTS. Exclusion criteria were good levator function, absent Bell’s phenomenon, and abnormal ocular motility. Follow-up period was 2 years. Functional outcome was measured from digital photos by analysis of upper eyelid margin position relative to the superior limbus and classified as very good (<3 mm, good (3–5 mm, poor (>5 mm, and recurrent. Aesthetic outcome was assessed in terms of lid contour, symmetry of eyelid height, and lid crease presence. Complications were also reported. Results: Failure rate (recurrence and complications was less in AFLS (P=0.035. Symmetrical lid height and good contour were more frequently attained by AFLS (P=0.007 and 0.047, respectively. However, the frequency of very good, good, poor, recurrence, lagopthalmos, ectropion, infection, and formed lid crease individually showed no statistically significant difference (P=0.252, 0.482, 1, 0.489, 0.438, 1, 0.618, and 0.506, respectively. Conclusion: AFLS is a better choice in surgery for patients with bilateral congenital ptosis because it has fewer complications and a lesser recurrence rate than GTS. Keywords: ptosis surgery, surgical outcomes, ptosis recurrence, lagophthalmos

  15. Current concepts and future approaches to the development of autologous/autogenous vaccines for veterinary use.

    Science.gov (United States)

    Tollis, M

    2004-01-01

    Current classification of autologous/autogenous (A/A) vaccines is commonly based on the concept of strain/antigen specificity associated with targeted treatment of a restricted number of animals. However, fulfilling these two conditions is not sufficient for immune-veterinary immunebiologicals to be excluded from the provisions of Directive 2001/82/EC. Indeed, non-inactivated A/A vaccines are not automatically considered out of the scope of the community code relating to veterinary medicinal products, in particular to immune-biologicals. As a major consequence of the "regulatory" exclusion from the requirements of EU rules, A/A vaccines can be usually manufactured and distributed without having obtained a marketing authorization by the competent authority of a Member State. Furthermore, strain specificity enables veterinarians to consider the use of these vaccines in quite a large variety of epidemiological circumstances where no "conventional" vaccines are yet available or are considered efficacious. In addition, in contrast to "conventional" vaccines, which are considered exclusively as a preventive tool against infectious diseases, A/A vaccines can also be used to treat "continuing" infections. Although the limited scientific value of these products and the poor investigations of the effector mechanisms involved are widely recognized, their use is still claimed in conditions where disorders in the immune system are suspected. Today, a more appropriate definition of A/A vaccines is one that takes into account their historical tradition and practical use, such as stable- or herd-specific vaccines, custom ("..ized") vaccines, therapeutic vaccines, pharmavaccines, vaccines used for biological therapy, etc. Although acknowledging the "regulatory autonomy" of A/A vaccines versus "conventional" vaccines, here it will be presented as an overview of the necessary points to consider, to guarantee an acceptable standard in the development and control of this particular

  16. Left in the Dust

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    NASA's Stardust spacecraft ended its seven-year voyage January 15 after a safe landing on earth, bringing back a capsule of comet particles and samples of interstellar dust that exceeded the loftiest of expectations of mission scientists. The ensuing studies of the cosmic treasure are expected to shed light on the origins of the solar system and earth itself.

  17. Cylindrically symmetric dust spacetime

    CERN Document Server

    Senovilla, J M M; Senovilla, Jose M. M.; Vera, Raul

    2000-01-01

    We present an explicit exact solution of Einstein's equations for an inhomogeneous dust universe with cylindrical symmetry. The spacetime is extremely simple but nonetheless it has new surprising features. The universe is ``closed'' in the sense that the dust expands from a big-bang singularity but recollapses to a big-crunch singularity. In fact, both singularities are connected so that the whole spacetime is ``enclosed'' within a single singularity of general character. The big-bang is not simultaneous for the dust, and in fact the age of the universe as measured by the dust particles depends on the spatial position, an effect due to the inhomogeneity, and their total lifetime has no non-zero lower limit. Part of the big-crunch singularity is naked. The metric depends on a parameter and contains flat spacetime as a non-singular particular case. For appropriate values of the parameter the spacetime is a small perturbation of Minkowski spacetime. This seems to indicate that flat spacetime may be unstable agai...

  18. Cylindrically symmetric dust spacetime

    Science.gov (United States)

    Senovilla, José M. M.

    2000-07-01

    We present an explicit exact solution of Einstein's equations for an inhomogeneous dust universe with cylindrical symmetry. The spacetime is extremely simple but nonetheless it has surprising new features. The universe is `closed' in the sense that the dust expands from a big-bang singularity but recollapses to a big-crunch singularity. In fact, both singularities are connected so that the whole spacetime is `enclosed' within a single singularity of general character. The big-bang is not simultaneous for the dust, and in fact the age of the universe as measured by the dust particles depends on the spatial position, an effect due to the inhomogeneity, and their total lifetime has no non-zero lower limit. Part of the big-crunch singularity is naked. The metric depends on a parameter and contains flat spacetime as a non-singular particular case. For appropriate values of the parameter the spacetime is a small perturbation of Minkowski spacetime. This seems to indicate that flat spacetime may be unstable against some global non-vacuum perturbations.

  19. Dust devil dynamics

    Science.gov (United States)

    Horton, W.; Miura, H.; Onishchenko, O.; Couedel, L.; Arnas, C.; Escarguel, A.; Benkadda, S.; Fedun, V.

    2016-06-01

    A self-consistent hydrodynamic model for the solar heating-driven onset of a dust devil vortex is derived and analyzed. The toroidal flows and vertical velocity fields are driven by an instability that arises from the inversion of the mass density stratification produced by solar heating of the sandy surface soil. The nonlinear dynamics in the primary temperature gradient-driven vertical airflows drives a secondary toroidal vortex flow through a parametric interaction in the nonlinear structures. While an external tangential shear flow may initiate energy transfer to the toroidal vortex flow, the nonlinear interactions dominate the transfer of vertical-radial flows into a fast toroidal flow. This secondary flow has a vertical vorticity, while the primary thermal gradient-driven flow produces the toroidal vorticity. Simulations for the complex nonlinear structure are carried out with the passive convection of sand as test particles. Triboelectric charging modeling of the dust is used to estimate the charging of the sand particles. Parameters for a Dust Devil laboratory experiment are proposed considering various working gases and dust particle parameters. The nonlinear dynamics of the toroidal flow driven by the temperature gradient is of generic interest for both neutral gases and plasmas.

  20. Bioactive Ca-P scaffolds used for bone reconstruction

    Institute of Scientific and Technical Information of China (English)

    RUAN Jian-ming(阮建明); ZOU Jian-peng(邹俭鹏); Goldie Elisabeth; LIU Bing(刘兵)

    2003-01-01

    Bioactive ceramic scaffolds HA*TCP, aimed to be applied in clinic, were evaluated both in vitro and in vivo models. HA*TCP was supposed as a completely biodegradable material and designed as a scaffold to be used for bone reconstruction or regeneration. Materials processing was proposed and physical properties as well as microstructure feature were characterized. Biological postulation of the relationship between seeding density and proliferation, and viability of human osteoblasts cultured on the porous HA*TCP were quantitatively measured. Bone reconstruction was investigated both in vitro and in vivo by using these biodegradable scaffolds with pore sizes ranged in 200-400 μm in diameter. The degradable scaffold supported cellular proliferation of seeded osteoblasts on the scaffold and shown normal differentiated function in vitro. Seeding density is an important factor for cell attachment and proliferation expression and has been considerably discussed. Suitable pore size of the scaffolds is required if promotion of bone reconstruction is desired. Clinical trials show that HA*TCP scaffolds are successful applied for bone reconstruction and regeneration and can be completely degraded in human body in 12 months. This approach suggests the feasibility of using porous HA*TCP scaffold materials for the transplantation of autogenous osteoblasts to regenerate bone tissue.

  1. Autogeneous Laser and Hybrid Laser Arc Welding of T-joint Low Alloy Steel with Fiber Laser Systems

    Science.gov (United States)

    Unt, A.; Lappalainen, E.; Salminen, A.

    This paper is focused on the welding of low alloy steels S355 and AH36 in thicknesses 6, 8 and 10 mm in T-joint configuration using either autogeneous laser welding or laser-arc hybrid welding (HLAW) with high power fiber lasers. The aim was to obtain understanding of the factors influencing the size of the fillet and weld geometry through methodologically studying effects of laser power, welding speed, beam alignment relative to surface, air gap, focal point position and order of processes (in case of HLAW) and to get a B quality class welds in all thicknesses after parameter optimization.

  2. Autogenic incision and terrace formation resulting from abrupt late-glacial base-level fall, lower Chippewa River, Wisconsin, USA

    Science.gov (United States)

    Faulkner, Douglas J.; Larson, Phillip H.; Jol, Harry M.; Running, Garry L.; Loope, Henry M.; Goble, Ronald J.

    2016-08-01

    A paucity of research exists regarding the millennial-scale response of inland alluvial streams to abrupt base-level fall. Studies of modern systems indicate that, over short time scales, the response is a diffusion-like process of upstream-propagating incision. In contrast, evidence from the lower Chippewa River (LCR), located in the upper Midwest of the USA, suggests that autogenic controls operating over time scales of several millennia can overwhelm diffusion, resulting in incision that is prolonged and episodic. During the Last Glacial Maximum, the LCR drained the Chippewa Lobe of the Laurentide Ice Sheet to the glacial upper Mississippi River (UMR). As a meltwater stream, it aggraded and filled its valley with glacial outwash, as did its largest tributaries, which were also meltwater streams. Its nonglacial tributaries aggraded, too, filling their valleys with locally derived sediment. During deglaciation, the UMR incised at least twice, abruptly lowering the LCR's base level - ~ 15 m at 16 ka or earlier and an additional 40 m at ca. 13.4 ka. Each of these base-level falls initiated incision of the LCR, led by upstream migrating knickpoints. The propagation of incision has, however, been a lengthy process. The optically stimulated luminescence (OSL) ages of terrace alluvium indicate that, by 13.5 ka, incision had advanced up the LCR only 15 km, and by 9 ka, only 55 km. The process has also been episodic, resulting in the formation of fill-cut terraces (inferred from GPR surveys and exposures of terrace alluvium) that are younger and more numerous in the upstream direction. Autogenic increases in sediment load and autogenic bed armoring, the result of periodic tributary-stream rejuvenation and preferential winnowing of fines by the incising river, may have periodically caused knickpoint migration and incision to slow and possibly stop, allowing lateral erosion and floodplain formation to dominate. A decline in sediment flux from stabilizing incised tributary

  3. Platelet-rich plasma diminishes calvarial bone repair associated with alterations in collagen matrix composition and elevated CD34+ cell prevalence.

    Science.gov (United States)

    Giovanini, Allan Fernando; Deliberador, Tatiana Miranda; Gonzaga, Carla Castiglia; de Oliveira Filho, Marco Antonio; Göhringer, Isabella; Kuczera, Juliane; Zielak, João Cesar; de Andrade Urban, Cícero

    2010-06-01

    The interaction between platelets and both type I and III collagens plays an important role in modulating platelet adhesion and aggregation, also contributing to the chemotaxis of CD34+ cells. The interaction with type III collagen can maintain high levels of collagen and alter the biology of bone repair when the PRP is used. The aim of this study was to evaluate the effect of platelet-rich plasma (PRP) and autograft on the presence of type III and type I collagens, the ratio between them, as well as the presence of CD34+ progenitor cells, while comparing these results by means of a histomorphometric analysis of the bone tissue. Four bone defects (8.0mm in diameter and 2.0mm in depth) were produced on the calvarium of 23 rabbits. The surgical defects were treated with either autogenous bone grafts, autogenous bone grafts with PRP and PRP alone. Animals were euthanized at 2, 4 or 6 weeks post-surgery. Histological, histomorphometric and immunohistochemical analyses were performed to assess repair time, as well as the expression of type I and III collagens, and number of progenitor CD34+ cells. Data were analyzed using the ANOVA and Student-Newman-Keuls test (alpha=5%). An enlarged granulation and medullary tissue areas in the PRP groups were observed. The use of PRP in this study hindered bone deposition, also enhanced type III to type I collagen ratio and the chemotaxis of CD34+ progenitor cells, similarly to a thrombogenic effect.

  4. Reuyl Crater Dust Avalanches

    Science.gov (United States)

    2002-01-01

    (Released 13 May 2002) The Science The rugged, arcuate rim of the 90 km crater Reuyl dominates this THEMIS image. Reuyl crater is at the southern edge of a region known to be blanketed in thick dust based on its high albedo (brightness) and low thermal inertia values. This thick mantle of dust creates the appearance of snow covered mountains in the image. Like snow accumulation on Earth, Martian dust can become so thick that it eventually slides down the face of steep slopes, creating runaway avalanches of dust. In the center of this image about 1/3 of the way down is evidence of this phenomenon. A few dozen dark streaks can be seen on the bright, sunlit slopes of the crater rim. The narrow streaks extend downslope following the local topography in a manner very similar to snow avalanches on Earth. But unlike their terrestrial counterparts, no accumulation occurs at the bottom. The dust particles are so small that they are easily launched into the thin atmosphere where they remain suspended and ultimately blow away. The apparent darkness of the avalanche scars is due to the presence of relatively dark underlying material that becomes exposed following the passage of the avalanche. Over time, new dust deposition occurs, brightening the scars until they fade into the background. Although dark slope streaks had been observed in Viking mission images, a clear understanding of this dynamic phenomenon wasn't possible until the much higher resolution images from the Mars Global Surveyor MOC camera revealed the details. MOC images also showed that new avalanches have occurred during the time MGS has been in orbit. THEMIS images will allow additional mapping of their distribution and frequency, contributing new insights about Martian dust avalanches. The Story The stiff peaks in this image might remind you of the Alps here on Earth, but they really outline the choppy edge of a large Martian crater over 50 miles wide (seen in the context image at right). While these aren

  5. Secondary aneurysmal bone cystic change of the chondroblastoma, mistaken for a primary aneurysmal bone cyst in the patella.

    Science.gov (United States)

    Chung, Jin Wha; Lee, Hwa Sung

    2014-03-01

    A 29-year-old woman complained of a 3-month history of left knee pain without trauma history. X-ray showed a well-defined osteolytic lesion with a sclerotic margin in the patella and magnetic resonance imaging showed T1-low and T2-high signal intensity with different fluid level. Our impression was an aneurysmal bone cyst. At surgery, the lesion was a blood-filled cystic cavity, surrounded by a gray or brownish tissue. Hemorrhagic soft tissues with recognizable bone fragments were observed. Curettage and autogenous bone graft was done. Microscopically, sheets of tumor cells were intermingled with some areas of eosinophilic chondroid matrix. The tumor cells showed oval-shaped nuclei with moderate eosinophilic cytoplasm. Several multinucleated giant cells and blood filled cystic cavities were observed. The final diagnosis was a chondroblastoma with a secondary aneurysmal bone cyst. At the post-operative 1.5-year follow-up, grafted bones were well incorporated radiographically and there were no recurrent evidence or any other abnormal symptoms.

  6. Bone cutting.

    Science.gov (United States)

    Giraud, J Y; Villemin, S; Darmana, R; Cahuzac, J P; Autefage, A; Morucci, J P

    1991-02-01

    Bone cutting has always been a problem for surgeons because bone is a hard living material, and many osteotomes are still very crude tools. Technical improvement of these surgical tools has first been their motorization. Studies of the bone cutting process have indicated better features for conventional tools. Several non-conventional osteotomes, particularly ultrasonic osteotomes are described. Some studies on the possible use of lasers for bone cutting are also reported. Use of a pressurised water jet is also briefly examined. Despite their advantages, non-conventional tools still require improvement if they are to be used by surgeons.

  7. Bone replacement following dental trauma prior to implant surgery--status.

    Science.gov (United States)

    Hallman, Mats; Mordenfeld, Arne; Strandkvist, Tomas

    2009-02-01

    Dento-alveolar trauma often leads to a need for reconstruction of the alveolar crest before an implant can be placed. Although autogenous bone grafts is considered the 'gold standard', this may be associated with patient morbidity and graft resorption. Consequently, the use of bone substitutes has increased. Today, a substantial number of biomaterials are available on the market, but only a few are well documented. The user should be aware that these biomaterials have different properties: resorbable or non-resorbable, time of resorption and resorption mechanism. The purpose of this review is to describe the function of various bone substitutes and indications for their use in reconstructive implant surgery and to give an overview of the current situation.

  8. Dust processing in elliptical galaxies

    CERN Document Server

    Hirashita, Hiroyuki; Villaume, Alexa; Srinivasan, Sundar

    2015-01-01

    We reconsider the origin and processing of dust in elliptical galaxies. We theoretically formulate the evolution of grain size distribution, taking into account dust supply from asymptotic giant branch (AGB) stars and dust destruction by sputtering in the hot interstellar medium (ISM), whose temperature evolution is treated by including two cooling paths: gas emission and dust emission (i.e. gas cooling and dust cooling). With our new full treatment of grain size distribution, we confirm that dust destruction by sputtering is too efficient to explain the observed dust abundance even if AGB stars continue to supply dust grains, and that, except for the case where the initial dust-to-gas ratio in the hot gas is as high as $\\sim 0.01$, dust cooling is negligible compared with gas cooling. However, we show that, contrary to previous expectations, cooling does not help to protect the dust; rather, the sputtering efficiency is raised by the gas compression as a result of cooling. We additionally consider grain grow...

  9. Brånemark and ITI dental implants in the human bone-grafted maxilla: a comparative evaluation

    DEFF Research Database (Denmark)

    Pinholt, Else M

    2003-01-01

    and the patients were followed between 20 and 67 months post implantation. The bone graft was transplanted to add bony volume in the maxillary sinus, the anterior floor of the nose and/or the alveolar ridge. After a healing period of 4(1/2) months, dental implants were inserted and left for healing for 8 months......The development of new characteristics concerning implant surface makes it interesting to clinically compare different implant systems in the bone-grafted maxilla. The aim of this evaluation was to compare clinical data of a two-staged procedure on the augmented extremely atrophic maxilla using...... either Brånemark- or ITI-fixures. In 25 patients (18 females, seven males) the severely atrophied maxilla was reconstructed with autogenous iliac or mandibular bone and either Brånemark or ITI implants. Seventy-eight Brånemark implants and 80 SLA-ITI implants were inserted in the augmented bone...

  10. A novel technique for guided bone regeneration using platelet-rich plasma and osteogenic progenitor cells: Literature-based rationale and case report.

    Science.gov (United States)

    Kwon, TaeHyun; Grieco, Peter C; Levin, Liran; Intini, Giuseppe

    2016-03-01

    Achieving predictable guided bone regeneration in critical size defects for future endosseous dental implant therapy poses a great challenge to clinicians. A novel technique utilizing autogenous osteogenic progenitor cells, calcium sulfate activated platelet-rich plasma in addition to particulate allograft was successfully used to augment a severely deficient maxillary anterior edentulous ridge. After 6 months of healing, satisfactory radiographic and clinical bone gain was noted with significant increase in alveolar ridge width. Endosseous implants were placed and restored successfully. The techniques with underlying clinical and biologic rationales are presented and discussed in this report.

  11. Experimental study on autologous iliac bone transplantation combined with PRF%自体髂骨复合PRF修复牙槽嵴裂的实验研究

    Institute of Scientific and Technical Information of China (English)

    周龙; 封兴华; 陆斌

    2013-01-01

    目的:将富血小板纤维蛋白(Platelet-rich fibrin,PRF)应用于牙槽嵴裂植骨手术,验证其是否能够减少植骨术后的骨吸收.方法:8~12月龄犬8只,以外科手术的方法制备双侧牙槽嵴裂模型,随机于两侧同期植入自体髂骨(对照组)及自体髂骨混合PRF(实验组).于术后当日、2个月、4个月时拍摄上颌骨CT,利用三维重建软件测量植骨区体积,计算骨吸收率.结果:术后2个月、4个月时实验组的骨吸收率明显小于对照组,行配对样本的t检验,P<0.01.结论:将PRF加入自体髂骨进行骨移植修复犬的牙槽嵴裂,在术后4个月的时间范围内,可以减少术后的骨吸收.%Objective We grafted the platelet-rich fibrin (PRF) mixed with autogenous iliac bone in the alveolar cleft and evaluated the bone resorption after operation. Methods 8 dogs (8-12 months) were created bilateral alveolar cleft by surgical operation, autogenous iliac bone(control group) and the PRF mixed with autogenous iliac bone(PRF group) were implanted into the defect of one side randomly and bone regeneration was investigated 2 months and 4 months after implantation. Results The bone resorption of the PRF group was lower than that of the control group at 2 months and 4 months,P<0.01. Conclusion Autogenous iliac bone grafting with PRF.which significantly reduces postoperative bone resorption on dog bilateral alveolar cleft model.

  12. Southern Dust Devils

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Released 9 July 2004 The atmosphere of Mars is a dynamic system. Water-ice clouds, fog, and hazes can make imaging the surface from space difficult. Dust storms can grow from local disturbances to global sizes, through which imaging is impossible. Seasonal temperature changes are the usual drivers in cloud and dust storm development and growth. Eons of atmospheric dust storm activity has left its mark on the surface of Mars. Dust carried aloft by the wind has settled out on every available surface; sand dunes have been created and moved by centuries of wind; and the effect of continual sand-blasting has modified many regions of Mars, creating yardangs and other unusual surface forms. In our final dust devil image we are again looking at the southern hemisphere of Mars. These tracks occur mainly on the northeast side of the topographic ridges. Of course, there are many exceptions, which makes understanding the dynamics that initiate the actual dust devil cyclone difficult. Image information: VIS instrument. Latitude -47.6, Longitude 317.3 East (42.7 West). 19 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed

  13. Plentiful Dust Devils

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Released 8 July 2004 The atmosphere of Mars is a dynamic system. Water-ice clouds, fog, and hazes can make imaging the surface from space difficult. Dust storms can grow from local disturbances to global sizes, through which imaging is impossible. Seasonal temperature changes are the usual drivers in cloud and dust storm development and growth. Eons of atmospheric dust storm activity has left its mark on the surface of Mars. Dust carried aloft by the wind has settled out on every available surface; sand dunes have been created and moved by centuries of wind; and the effect of continual sand-blasting has modified many regions of Mars, creating yardangs and other unusual surface forms. These dust devil tracks occur on the northern plains of Mars. The majority of the surface seen in the image has been affected by the passage of dust devils. Image information: VIS instrument. Latitude -54.6, Longitude 79.3 East (280.7 West). 19 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are

  14. A comparative evaluation of freeze dried bone allograft and decalcified freeze dried bone allograft in the treatment of intrabony defects: A clinical and radiographic study

    Directory of Open Access Journals (Sweden)

    Rajat Gothi

    2015-01-01

    Full Text Available Background: Ideal graft material for regenerative procedures is autogenous bone graft but the major disadvantage with this graft is the need for a secondary surgical site to procure donor material and the frequent lack of intraoral donor site to obtain sufficient quantities of autogenous bone for multiple or deep osseous defects. Hence, to overcome these disadvantages, bone allografts were developed as an alternative source of graft material. Materials and Methods: In 10 patients with chronic periodontitis, 20 bilateral infrabony defects were treated with freeze dried bone allograft (FDBA-Group A and decalcified freeze dried bone allograft (DFDBA-Group B. Clinical and radiographic parameters were assessed preoperatively and at 3 months and 6 months postoperatively. Data thus obtained was subjected to statistical analysis. Results: Significant improvement in the reduction in probing depth and relative attachment level (RAL from the baseline to 3 months to baseline to 6 months in group A and group B, which was statistically significant but no statistically significant reduction was seen between 3 months and 6 months. On inter-group comparison, no significant differences were observed at all-time points. In adjunct to the probing depth and RAL, the radiographic area of the defect showed a similar trend in intra-group comparison and no significant difference was seen on inter-group comparison at all-time points. Conclusions: Within the limitations of the current study, it can be concluded that DFDBA did not show any improvement in the clinical and radiographic parameters in the treatment of the intrabony defects as compared to FDBA.

  15. Audio-Visual and Autogenic Relaxation Alter Amplitude of Alpha EEG Band, Causing Improvements in Mental Work Performance in Athletes.

    Science.gov (United States)

    Mikicin, Mirosław; Kowalczyk, Marek

    2015-09-01

    The aim of the present study was to investigate the effect of regular audio-visual relaxation combined with Schultz's autogenic training on: (1) the results of behavioral tests that evaluate work performance during burdensome cognitive tasks (Kraepelin test), (2) changes in classical EEG alpha frequency band, neocortex (frontal, temporal, occipital, parietal), hemisphere (left, right) versus condition (only relaxation 7-12 Hz). Both experimental (EG) and age-and skill-matched control group (CG) consisted of eighteen athletes (ten males and eight females). After 7-month training EG demonstrated changes in the amplitude of mean electrical activity of the EEG alpha bend at rest and an improvement was significantly changing and an improvement in almost all components of Kraepelin test. The same examined variables in CG were unchanged following the period without the intervention. Summing up, combining audio-visual relaxation with autogenic training significantly improves athlete's ability to perform a prolonged mental effort. These changes are accompanied by greater amplitude of waves in alpha band in the state of relax. The results suggest usefulness of relaxation techniques during performance of mentally difficult sports tasks (sports based on speed and stamina, sports games, combat sports) and during relax of athletes.

  16. Workability’s recreation methodic with application of cupping massage and autogenic training of women student teams’ basketball players

    Directory of Open Access Journals (Sweden)

    Kozina Zh.L.

    2015-04-01

    Full Text Available Purpose: to experimentally subsituate effectiveness of non traditional complex methodic of recreation in female basketball players’ training process. Material: 22 basketball players of women student’s team participated in the research. Pedagogic testing was conducted by 12 tests in special physical and technical fitness. Psycho-physiological testing was conducted by program PSYCHO-DIAGNOSTIC. Groups were trained by identical programs during 9 weeks. Results: we authors observed increased physical and technical fitness of basketball players. Besides, quantity of mistakes in response to visual irritator reduced. It indirectly witnesses about strengthening of nervous processes. There was registered influence of mind on quality of organism’s recreation after physical loads. Conclusions: the authors recommend methodic of cupping massage, combined with autogenic training. Autogenic training implies repeated pronouncing by instructor (or independently by sportswomen of text, describing coming turn by turn natural images. Peculiarities of massage were influence of massage passes on muscles and ligaments. Cupping massage was used after warming up classic massage techniques.

  17. Treatment concepts for the posterior maxilla and mandible: short implants versus long implants in augmented bone

    Science.gov (United States)

    2017-01-01

    The aim of this narrative review is to describe treatment options for the posterior regions of the mandible and the maxilla, comparing short implants vs. longer implants in an augmented bone. The dental literature was screened for treatment options enabling the placement of dental implants in posterior sites with a reduced vertical bone height in the maxilla and the mandible. Short dental implants have been increasingly used recently, providing a number of advantages including reduced patient morbidity, shorter treatment time, and lower costs. In the posterior maxilla, sinus elevation procedures were for long considered to be the gold standard using various bone substitute materials and rendering high implant survival rates. More recently, implants were even placed without any further use of bone substitute materials, but the long-term outcomes have yet to be documented. Vertical bone augmentation procedures in the mandible require a relatively high level of surgical skill and allow the placement of standard-length dental implants by the use of autogenous bone blocks. Both treatment options, short dental implants, and standard-length implants in combination with vertical bone augmentation procedures, appear to result in predictable outcomes in terms of implant survival rates. According to recent clinical studies comparing the therapeutic options of short implants vs. long implants in augmented bone, the use of short dental implants leads to a number of advantages for the patients and the clinician. PMID:28261519

  18. Treatment concepts for the posterior maxilla and mandible: short implants versus long implants in augmented bone.

    Science.gov (United States)

    Thoma, Daniel Stefan; Cha, Jae-Kook; Jung, Ui-Won

    2017-02-01

    The aim of this narrative review is to describe treatment options for the posterior regions of the mandible and the maxilla, comparing short implants vs. longer implants in an augmented bone. The dental literature was screened for treatment options enabling the placement of dental implants in posterior sites with a reduced vertical bone height in the maxilla and the mandible. Short dental implants have been increasingly used recently, providing a number of advantages including reduced patient morbidity, shorter treatment time, and lower costs. In the posterior maxilla, sinus elevation procedures were for long considered to be the gold standard using various bone substitute materials and rendering high implant survival rates. More recently, implants were even placed without any further use of bone substitute materials, but the long-term outcomes have yet to be documented. Vertical bone augmentation procedures in the mandible require a relatively high level of surgical skill and allow the placement of standard-length dental implants by the use of autogenous bone blocks. Both treatment options, short dental implants, and standard-length implants in combination with vertical bone augmentation procedures, appear to result in predictable outcomes in terms of implant survival rates. According to recent clinical studies comparing the therapeutic options of short implants vs. long implants in augmented bone, the use of short dental implants leads to a number of advantages for the patients and the clinician.

  19. [House dust mite allergy].

    Science.gov (United States)

    Carrard, A; Pichler, C

    2012-04-01

    House dust mites can be found all over the world where human beings live independent from the climate. Proteins from the gastrointestinal tract- almost all known as enzymes - are the allergens which induce chronic allergic diseases. The inhalation of small amounts of allergens on a regular base all night leads to a slow beginning of the disease with chronically stuffed nose and an exercise induced asthma which later on persists. House dust mites grow well in a humid climate - this can be in well isolated dwellings or in the tropical climate - and nourish from human skin dander. Scales are found in mattresses, upholstered furniture and carpets. The clinical picture with slowly aggravating complaints leads quite often to a delayed diagnosis, which is accidently done on the occasion of a wider spectrum of allergy skin testing. The beginning of a medical therapy with topical steroids as nasal spray or inhalation leads to a fast relief of the complaints. Although discussed in extensive controversies in the literature - at least in Switzerland with the cold winter and dry climate - the recommendation of house dust mite avoidance measures is given to patients with good clinical results. The frequent ventilation of the dwelling with cold air in winter time cause a lower indoor humidity. Covering encasings on mattresses, pillow, and duvets reduces the possibility of chronic contact with mite allergens as well as the weekly changing the bed linen. Another option of therapy is the specific immunotherapy with extracts of house dust mites showing good results in children and adults. Using recombinant allergens will show a better quality in diagnostic as well as in therapeutic specific immunotherapy.

  20. Treatment of Radial Nonunion with Corticocancellous Bone Graft and Fascia of Anterolateral Thigh Free Flap: The Wrap Technique

    Science.gov (United States)

    Ronga, Mario; Sallam, Davide; Fagetti, Alessandro; Valdatta, Luigi; Cherubino, Paolo

    2016-01-01

    Summary: The management of nonunion of the forearm bones is a challenging task. Multiple factors have been associated with the establishment of forearm nonunion, such as the fracture position and complexity, general condition of the patient, and the previously utilized surgical technique. The optimal surgical treatment of a bone gap remains a subject of discussion. Autogenous corticocancellous bone grafts and vascularized bone flaps have been used with differing results. The authors describe a technique for the treatment of posttraumatic nonunion of the radius with a 5-cm bone gap using the free anterolateral thigh fascial flap wrapped around a tricortical iliac bone graft. The fracture healed after 5 weeks. The use of a vascularized tissue wrapped around the bone graft resulted in a well-healed bone and no signs of resorption after 2 years of follow-up. A bone graft wrapped by a fascial flap could magnify the restorative effect on the bone defect because of its dual role of constructing vascularization and inducing tissue regeneration.

  1. Bone Augmentation in Rabbit Tibia Using Microfixed Cobalt-Chromium Membranes with Whole Blood and Platelet-Rich Plasma

    Directory of Open Access Journals (Sweden)

    Oscar A. Decco

    2015-07-01

    Full Text Available Background: Bone augmentation is a subject of intensive investigation in regenerative bone medicine and constitutes a clinical situation in which autogenous bone grafts or synthetic materials are used to aid new bone formation. Method: Based on a non-critical defect, Co-Cr barrier membranes were placed on six adult Fauve de Bourgogne rabbits, divided into two groups: whole blood and PRP. Three densitometric controls were performed during the experiment. The animals were euthanized at 30, 45, 60, and 110 days. The presence of newly formed bone was observed. Samples for histological studies were taken from the augmentation center. Results: External and internal bone tissue augmentation was observed in almost all cases. Significant differences between PRP- and whole blood–stimulated bone augmentation were not observed. At 60 days, bones with PRP presented higher angiogenesis, which may indicate more proliferation and cellular activity. Conclusion: PRP activates the bone regeneration process under optimized conditions by stimulation of osteoblast proliferation after six weeks, when a significant difference in cellular activity was observed. Membranes could stimulate bone augmentation at the site of placement and in the surrounding areas.

  2. A coal dust burner

    Energy Technology Data Exchange (ETDEWEB)

    Vakhrshev, B.M.; Khasnullin, I.G.; Krauze, Ye.G.; Ushakov, Yu.A.; Zinovyev, V.G.

    1982-01-01

    The burner for combustion of coal dust fuel, primarily, in rotating furnaces, contains coaxially disposed pipes, a branch pipe for feeding in the air mixture and a rotating mechanism. The first two pipes are switched in to an air source. The third pipe on the input end has an oblique section and the pipe may be rotated around an axis by a mechanism. The first pipe has ports and it may be moved in an axial direction. By installing the third pipe in the first and second positions, it is possible to direct the dust coming from the branch pipe along the central (the larger part of the dust) or the central pipe, respectively, which makes it possible to regulate the configuration of the torch and its temperature. Hot air is sucked from the furnace through the ports in the perforated first pipe to the mouth of the burner, which makes it possible to intensify combustion. By moving the fifitpipe to the right it is possible to overlap the ports with the projections and to rule out suction of the air. The possibility of regulating combustion in wide ranges makes it possible to reduce the expenditure of fuel by 2 to 3 percent.

  3. Case report: a case of intractable Meniere's disease treated with autogenic training

    Directory of Open Access Journals (Sweden)

    Nakai Kimiko

    2008-01-01

    Full Text Available Abstract Background Psychological stress plays an important role in the onset and course of Meniere's disease. Surgical therapy and intratympanic gentamicin treatment are options for cases that are intractable to conventional medical therapy. Psychotherapy, however, including autogenic training (AT, which can be used for general relaxation, is not widely accepted. This paper describes the successful administration of AT in a subject suffering from intractable Meniere's disease. Case presentation A 51-year-old male patient has suffered from fluctuating right sensorineural hearing loss with vertigo since 1994. In May 2002, he was first admitted to our hospital due to a severe vertigo attack accompanied by right sensorineural hearing loss. Spontaneous nystagmus toward the right side was observed. Since April 2004, he has experienced vertigo spells with right-sided tinnitus a few times per month that are intractable to conventional medical therapy. After four months, tympanic tube insertion was preformed in the right tympanic membrane. Intratympanic injection of dexamethasone was ineffective. He refused Meniett therapy and intratympanic gentamicin injection. In addition to his vertigo spells, he suffered from insomnia, tinnitus, and anxiety. Tranquilizers such as benzodiazepines and antidepressants such as serotonin selective re-uptake inhibitors (SSRIs failed to stop the vertigo and only slightly improved his insomnia. In December 2006, the patient began psychological counseling with a psychotherapist. After brief psychological counseling along with cognitive behavior therapy (CBT, he began AT. He diligently and regularly continued his AT training in his home according to a written timetable. His insomnia, tinnitus, and vertigo spells disappeared within a few weeks after only four psychotherapy sessions. In order to master the six standard formulas of AT, he underwent two more sessions. Thereafter, he underwent follow-up for 9 months with no

  4. Dust, Climate, and Human Health

    Science.gov (United States)

    Maynard, N. G.

    2003-12-01

    Air pollution from both natural and anthropogenic causes is considered to be one of the most serious world-wide environment-related health problems, and is expected to become worse with changes in the global climate. Dust storms from the atmospheric transport of desert soil dust that has been lifted and carried by the winds - often over significant distances - have become an increasingly important emerging air quality issue for many populations. Recent studies have shown that the dust storms can cause significant health impacts from the dust itself as well as the accompanying pollutants, pesticides, metals, salt, plant debris, and other inorganic and organic materials, including viable microorganisms (bacteria, viruses and fungi). For example, thousands of tons of Asian desert sediments, some containing pesticides and herbicides from farming regions, are commonly transported into the Arctic during dust storm events. These chemicals have been identified in animal and human tissues among Arctic indigenous populations. Millions of tons of airborne desert dust are being tracked by satellite imagery, which clearly shows the magnitude as well as the temporal and spatial variability of dust storms across the "dust belt" regions of North Africa, the Middle East, and China. This paper summarizes the most recent findings on the effects of airborne desert dust on human health as well as potential climate influences on dust and health

  5. Clouds and Dust Storms

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Released 2 July 2004 The atmosphere of Mars is a dynamic system. Water-ice clouds, fog, and hazes can make imaging the surface from space difficult. Dust storms can grow from local disturbances to global sizes, through which imaging is impossible. Seasonal temperature changes are the usual drivers in cloud and dust storm development and growth. Eons of atmospheric dust storm activity has left its mark on the surface of Mars. Dust carried aloft by the wind has settled out on every available surface; sand dunes have been created and moved by centuries of wind; and the effect of continual sand-blasting has modified many regions of Mars, creating yardangs and other unusual surface forms. This image was acquired during mid-spring near the North Pole. The linear water-ice clouds are now regional in extent and often interact with neighboring cloud system, as seen in this image. The bottom of the image shows how the interaction can destroy the linear nature. While the surface is still visible through most of the clouds, there is evidence that dust is also starting to enter the atmosphere. Image information: VIS instrument. Latitude 68.4, Longitude 180 East (180 West). 38 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote

  6. Bone x-ray

    Science.gov (United States)

    ... or broken bone Bone tumors Degenerative bone conditions Osteomyelitis (inflammation of the bone caused by an infection) ... Multiple myeloma Osgood-Schlatter disease Osteogenesis imperfecta Osteomalacia Osteomyelitis Paget disease of the bone Rickets X-ray ...

  7. Chondroblastoma in a metatarsal treated with autogenous fibular graft: a case report.

    Science.gov (United States)

    Dhatt, Sarvdeep S; Bhagwat, Kishan R; Kumar, Vishal; Dhillon, Mandeep Singh

    2012-01-01

    Chondroblastoma is a relatively rare tumor that mimics giant cell tumor and displays a predilection for long bones. In the present report, we describe the case of a benign chondroblastoma localized to the second metatarsal in a 20-year-old male who presented with a 2-year history of painless left foot swelling. Treatment of the tumor involved excision of the second metatarsal with use of an autologous structural fibular bone graft to stabilize the metatarsus and second toe. After 27 months of follow-up, the patient was ambulating well in regular shoes, with no clinical or radiographic evidence of tumor recurrence.

  8. Bone mesenchymal stem cell sheet transplantation combined with autologous iliac bone for repair of alveolar cleft%骨髓间充质干细胞膜片复合自体髂骨移植修复牙槽嵴裂

    Institute of Scientific and Technical Information of China (English)

    沈悦; 马海英; 张彦升; 王娟; 时炳正

    2014-01-01

    BACKGROUND:Autogenous iliac bone graft for repair of alveolar cleft often cannot achieve a stable therapeutic effect, and the graft resorption rate varies with each individual that is influenced by many factors. OBJECTIVE:To observe the bone resorption after bone marrow mesenchymal stem cel sheet transplantation with autogenous iliac cancelous bone for alveolar cleft repair. METHODS:Bilateral alveolar cleft models were prepared in dogs. Using the self-control method, bone marrow mesenchymal stem cel sheet combined with autogenous iliac bone (experimental group) and autogenous iliac bone alone (control group) were respectively implanted into the bilateral alveolar clefts. Mandible CT and microCT were used to compare the bone resorption rate, bone volume fraction, trabecular thickness, trabecular separation, and bone mineral density. RESULTS AND CONCLUSION:The bone resorption rate was significantly lower in the experimental group than the control group at 3 and 6 postoperative months (P 0.05). These findings indicate that bone marrow mesenchymal stem cel sheet transplantation combined with autogenous iliac bone graft can reduce bone resorption rate and meanwhile, promote new bone formation.%背景:临床上使用自体髂骨移植方法修复牙槽嵴裂,常常不能获得稳定的治疗效果,移植骨吸收率因人而异,受到许多因素的影响。  目的:观察骨髓间充质干细胞膜片复合自体髂骨松质骨块移植修复牙槽嵴裂术后的骨吸收情况。  方法:制备实验犬双侧牙槽嵴裂模型,采用自体对照的办法,在实验犬上颌骨两侧的裂隙分别植入骨髓间充质干细胞膜片复合犬自体髂骨骨块(实验组)和单纯犬自体髂骨骨块(对照组)。通过颌骨CT及micro CT对植骨区的骨吸收率、骨体积分数、骨小梁厚度、骨小梁分离度、骨密度进行比较。  结果与结论:术后3,6个月时实验组的骨吸收率明显低于对照组,差

  9. Optimizing Saharan dust CALIPSO retrievals

    Directory of Open Access Journals (Sweden)

    V. Amiridis

    2013-06-01

    Full Text Available We demonstrate improvements in CALIPSO dust extinction retrievals over North Africa and Europe when corrections are applied regarding the Saharan dust lidar ratio assumption, the separation of dust portion in detected dust mixtures, and the averaging scheme introduced in the Level 3 CALIPSO product. First, a universal, spatially constant lidar ratio of 58 sr instead of 40 sr is applied to individual Level 2 dust-related backscatter products. The resulting aerosol optical depths show an improvement compared with synchronous and co-located AERONET measurements. An absolute bias of the order of −0.03 has been found, improving on the statistically significant biases of the order of −0.10 reported in the literature for the original CALIPSO product. When compared with the MODIS co-located AOD product, the CALIPSO negative bias is even less for the lidar ratio of 58 sr. After introducing the new lidar ratio for the domain studied, we examine potential improvements to the climatological CALIPSO Level 3 extinction product: (1 by introducing a new methodology for the calculation of pure dust extinction from dust mixtures and (2 by applying an averaging scheme that includes zero extinction values for the non-dust aerosol types detected. The scheme is applied at a horizontal spatial resolution of 1° × 1° for ease of comparison with the instantaneous and co-located dust extinction profiles simulated by the BSC-DREAM8b dust model. Comparisons show that the extinction profiles retrieved with the proposed methodology reproduce the well-known model biases per sub-region examined. The very good agreement of the proposed CALIPSO extinction product with respect to AERONET, MODIS and the BSC-DREAM8b dust model, makes this dataset an ideal candidate for the provision of an accurate and robust multi-year dust climatology over North Africa and Europe.

  10. Analysis on Application Bottleneck of Repairing Bone Defects with Tissue Engineered Bone%组织工程骨修复骨缺损的应用瓶颈分析

    Institute of Scientific and Technical Information of China (English)

    李凯

    2012-01-01

    Bone defects caused by bone cancer treatment are common in clinical, however the only way to repair the defects is bone graft. According to sources, the bone graft material can be divided into autogenous bone, allograft bone ,xenograft bone and artificial bone substitute materials. The rise of bone tissue engineering brings new options for the treatment of bone defects. The use of artificial bone tissue engineering training not only fixes the large area of bone defect, but also can be prepared and shaped in large quantity according to need,which makes it an ideal bone repair material. Here is to make a review' on the application status of tissue engineered bone in the treatment of bone defects.%骨肿瘤的治疗导致骨缺损很常见,修复缺损的方法是采取骨移植.骨移植材料根据来源大致可分为自体骨、同种异体骨、异种骨和人工骨替代材料.骨组织工程的兴起为骨缺损的治疗带来新的选择.利用骨组织工程培养的人工骨不仅可以修复大面积骨缺损,而且可以按需塑形并大量制备,是一种理想的骨修复材料.现就组织工程骨在治疗骨缺损中的应用现状进行综述.

  11. Bone pain

    DEFF Research Database (Denmark)

    Frost, Charlotte Ørsted; Hansen, Rikke Rie; Heegaard, Anne-Marie

    2016-01-01

    Skeletal conditions are common causes of chronic pain and there is an unmet medical need for improved treatment options. Bone pain is currently managed with disease modifying agents and/or analgesics depending on the condition. Disease modifying agents affect the underlying pathophysiology...... of the disease and reduce as a secondary effect bone pain. Antiresorptive and anabolic agents, such as bisphosphonates and intermittent parathyroid hormone (1-34), respectively, have proven effective as pain relieving agents. Cathepsin K inhibitors and anti-sclerostin antibodies hold, due to their disease...... modifying effects, promise of a pain relieving effect. NSAIDs and opioids are widely employed in the treatment of bone pain. However, recent preclinical findings demonstrating a unique neuronal innervation of bone tissue and sprouting of sensory nerve fibers open for new treatment possibilities....

  12. Bone graft

    Science.gov (United States)

    ... around the area. The bone graft can be held in place with pins, plates, or screws. Why ... Orthopaedic Surgery, San Francosco, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the ...

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

    Directory of Open Access Journals (Sweden)

    Ozgur Pilanci

    2013-06-01

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

  14. Dust coagulation in ISM

    Science.gov (United States)

    Chokshi, Arati; Tielens, Alexander G. G. M.; Hollenbach, David

    1989-01-01

    Coagulation is an important mechanism in the growth of interstellar and interplanetary dust particles. The microphysics of the coagulation process was theoretically analyzed as a function of the physical properties of the coagulating grains, i.e., their size, relative velocities, temperature, elastic properties, and the van der Waal interaction. Numerical calculations of collisions between linear chains provide the wave energy in individual particles and the spectrum of the mechanical vibrations set up in colliding particles. Sticking probabilities are then calculated using simple estimates for elastic deformation energies and for the attenuation of the wave energy due to absorption and scattering processes.

  15. Flying Through Dust From Asteroids

    Science.gov (United States)

    Kohler, Susanna

    2016-11-01

    How can we tell what an asteroid is made of? Until now, weve relied on remote spectral observations, though NASAs recently launched OSIRIS-REx mission may soon change this by landing on an asteroid and returning with a sample.But what if we could learn more about the asteroids near Earth without needing to land on each one? It turns out that we can by flying through their dust.The aerogel dust collector of the Stardust mission. [NASA/JPL/Caltech]Ejected CluesWhen an airless body is impacted by the meteoroids prevalent throughout our solar system, ejecta from the body are flung into the space around it. In the case of small objects like asteroids, their gravitational pull is so weak that most of the ejected material escapes, forming a surrounding cloud of dust.By flying a spacecraft through this cloud, we could perform chemical analysis of the dust, thereby determining the asteroids composition. We could even capture some of the dust during a flyby (for example, by using an aerogel collector like in the Stardust mission) and bring it back home to analyze.So whats the best place to fly a dust-analyzing or -collecting spacecraft? To answer this, we need to know what the typical distribution of dust is around a near-Earth asteroid (NEA) a problem that scientists Jamey Szalay (Southwest Research Institute) and Mihly Hornyi (University of Colorado Boulder) address in a recent study.The colors show the density distribution for dust grains larger than 0.3 m around a body with a 10-km radius. The distribution is asymmetric, with higher densities on the apex side, shown here in the +y direction. [Szalay Hornyi 2016]Moon as a LaboratoryTo determine typical dust distributions around NEAs, Szalay and Hornyi first look at the distribution of dust around our own Moon, caused by the same barrage of meteorites wed expect to impact NEAs. The Moons dust cloud was measured in situ in 2013 and 2014 by the Lunar Dust Experiment (LDEX) on board the Lunar Atmosphere and Dust Environment

  16. [Biological effect of wood dust].

    Science.gov (United States)

    Maciejewska, A; Wojtczak, J; Bielichowska-Cybula, G; Domańska, A; Dutkiewicz, J; Mołocznik, A

    1993-01-01

    The biological effect of exposure to wood dust depends on its composition and the content of microorganisms which are an inherent element of the dust. The irritant and allergic effects of wood dust have been recognised for a long time. The allergic effect is caused by the wood dust of subtropical trees, e.g. western red cedar (Thuja plicata), redwood (Sequoia sempervirens), obeche (Triplochiton scleroxylon), cocabolla (Dalbergia retusa) and others. Trees growing in the European climate such as: larch (Larix), walnut (Juglans regia), oak (Quercus), beech (Fagus), pine (Pinus) cause a little less pronounced allergic effect. Occupational exposure to irritative or allergic wood dust may lead to bronchial asthma, rhinitis, alveolitis allergica, DDTS (Organic dust toxic syndrome), bronchitis, allergic dermatitis, conjunctivitis. An increased risk of adenocarcinoma of the sinonasal cavity is an important and serious problem associated with occupational exposure to wood dust. Adenocarcinoma constitutes about half of the total number of cancers induced by wood dust. An increased incidence of the squamous cell cancers can also be observed. The highest risk of cancer applies to workers of the furniture industry, particularly those dealing with machine wood processing, cabinet making and carpentry. The cancer of the upper respiratory tract develops after exposure to many kinds of wood dust. However, the wood dust of oak and beech seems to be most carcinogenic. It is assumed that exposure to wood dust can cause an increased incidence of other cancers, especially lung cancer and Hodgkin's disease. The adverse effects of microorganisms, mainly mould fungi and their metabolic products are manifested by alveolitis allergica and ODTS. These microorganisms can induce aspergillomycosis, bronchial asthma, rhinitis and allergic dermatitis.

  17. Low Bone Density

    Science.gov (United States)

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

  18. Autogenic-Feedback Training (AFT) as a preventive method for space motion sickness: Background and experimental design

    Science.gov (United States)

    Cowings, Patricia S.; Toscano, William B.

    1993-01-01

    Finding an effective treatment for the motion sickness-like symptoms that occur in space has become a high priority for NASA. The background research is reviewed and the experimental design of a formal life sciences shuttle flight experiment designed to prevent space motion sickness in shuttle crew members is presented. This experiment utilizes a behavioral medicine approach to solving this problem. This method, Autogenic-Feedback Training (AFT), involves training subjects to voluntarily control several of their own physiological responses to environmental stressors. AFT has been used reliably to increase tolerance to motion sickness during ground-based tests in over 200 men and women under a variety of conditions that induce motion sickness, and preliminary evidence from space suggests that AFT may be an effective treatment for space motion sickness as well. Proposed changes to this experiment for future manifests are included.

  19. Erosion of dust aggregates

    CERN Document Server

    Seizinger, Alexander; Kley, Wilhelm

    2013-01-01

    Aims: The aim of this work is to gain a deeper insight into how much different aggregate types are affected by erosion. Especially, it is important to study the influence of the velocity of the impacting projectiles. We also want to provide models for dust growth in protoplanetary disks with simple recipes to account for erosion effects. Methods: To study the erosion of dust aggregates we employed a molecular dynamics approach that features a detailed micro-physical model of the interaction of spherical grains. For the first time, the model has been extended by introducing a new visco-elastic damping force which requires a proper calibration. Afterwards, different sample generation methods were used to cover a wide range of aggregate types. Results: The visco-elastic damping force introduced in this work turns out to be crucial to reproduce results obtained from laboratory experiments. After proper calibration, we find that erosion occurs for impact velocities of 5 m/s and above. Though fractal aggregates as ...

  20. Of data and dust

    CERN Multimedia

    Stephanie Hills

    2016-01-01

    The traditional image of an archive is one of dusty old boxes, books and papers. When your archive is digital, dust spells disaster. An innovative environmental sensor designed and built by a CERN IT specialist has become an essential element in the Laboratory’s data-preservation strategy.   The novel air particle monitoring sensor designed by CERN's Julien Leduc. CERN’s archive holds more than 130 petabytes of data from past and present high-energy physics experiments. Some of it is 40 years old, most of it needs to be kept forever, and all of it is held on tape cartridges (over 20,000 of them). The cartridges are held inside tape libraries with robotic arms that load them into tape drives where they can be read and written. Tape cartridges have many advantages over other data storage media, notably cost and long-term reliability, but topping the list of drawbacks is their vulnerability to contamination from airborne dust particles; a tiny piece of g...

  1. Charged Dust Aggregate Interactions

    Science.gov (United States)

    Matthews, Lorin; Hyde, Truell

    2015-11-01

    A proper understanding of the behavior of dust particle aggregates immersed in a complex plasma first requires a knowledge of the basic properties of the system. Among the most important of these are the net electrostatic charge and higher multipole moments on the dust aggregate as well as the manner in which the aggregate interacts with the local electrostatic fields. The formation of elongated, fractal-like aggregates levitating in the sheath electric field of a weakly ionized RF generated plasma discharge has recently been observed experimentally. The resulting data has shown that as aggregates approach one another, they can both accelerate and rotate. At equilibrium, aggregates are observed to levitate with regular spacing, rotating about their long axis aligned parallel to the sheath electric field. Since gas drag tends to slow any such rotation, energy must be constantly fed into the system in order to sustain it. A numerical model designed to analyze this motion provides both the electrostatic charge and higher multipole moments of the aggregate while including the forces due to thermophoresis, neutral gas drag, and the ion wakefield. This model will be used to investigate the ambient conditions leading to the observed interactions. This research is funded by NSF Grant 1414523.

  2. Intra-eyebrow frontalis suspension using inverted Y-shaped short autogenous fascia lata for blepharoptosis with poor levator function.

    Science.gov (United States)

    Shimizu, Yusuke; Nagasao, Tomohisa; Shido, Hirokazu; Fujii, Takako; Kato, Tatsuya; Aoki, Marie; Takada, Keiko; Kishi, Kazuo

    2015-01-01

    Frontalis suspension using autogenous fascia lata is a common procedure for blepharoptosis with poor levator function. However, donor-site morbidity associated with fascia lata harvest cannot be ignored. In conventional procedures, the required length of the fascia lata is usually >5-12 cm with a lateral thigh skin incision of approximately 5 cm or more. The present study introduces a new frontalis suspension procedure in which the required size (length and width) of the fascia lata and length of lateral thigh incision is much smaller. The harvested fascia lata is tailored to an inverted Y shape and the separated caudal legs are fixed to the tarsus while the cephalic end is grafted inside the eyebrow through a suborbital septum tunnel. In the present study, 11 patients who underwent the new procedure with a minimum of 6 months of follow-up were evaluated. The average length and width of the harvested fascia lata in unilateral ptosis cases were 2.85 and 0.89 cm, respectively. The average length of the lateral thigh incision was 1.25 cm. The margin reflex distance improved in all cases at 6 months postoperatively. The cosmetic result was graded as good to excellent in most of the patients. Trichiasis, widened donor scar, and eyebrow notch were noted as complications. The present method is a good alternative for the treatment of blepharoptosis with poor levator function. It potentially reduces donor-site morbidity as compared with conventional frontalis muscle suspension procedures using autogenous fascia lata.

  3. Significance of changes in transforming growth factor-β mRNA levels in autogenous vein grafts

    Institute of Scientific and Technical Information of China (English)

    尤文俊; 萧明第; 袁忠祥

    2004-01-01

    Background This study was designed to investigate changes in mRNA levels of transforming growth factor-β(TGF-β), collagen Ⅰ, and collagen Ⅲ in autogenous vein grafts. Methods Twenty-four New Zealand rabbits were randomly divided into 4 groups with 6 rabbits each. The external jugular veins of the New Zealand rabbits were harvested and grafted into the ipsilateral carotid artery. All rabbits were fed with a standard diet. After the operation, the rabbits were sacrificed at 1, 2, 3, or 4 weeks. TGF-β, collagen Ⅰ, and collagen Ⅲ mRNA levels in the venous grafts were measured by semiquantitative methods at every time point. The contralateral external jugular veins were also harvested and analyzed as controls. Glyceraldehyde-3-phosphate dehydrogenase was used as an internal standard to normalize all samples for potential variations in mRNA content. In order to observe the expression of TGF-β protein, immunohistochemical SABC methods were used. Results One week postoperation, the mRNA level of TGF-β was upregulated to 1.73±0.19 in the vein graft and 1.21±0.16 in the control vein (P<0.01). High mRNA levels were maintained until week 4 postoperation. The mRNA levels of collagen Ⅰ and collagen Ⅲ were also significantly increased to 2.18±0.21 versus 1.12±0.24 and 1.08±0.13 versus 0.83±0.12, respectively (P<0.05). Immunohistochemical staining revealed a higher density of TGF-β expression in the vein grafts.Conclusions An uninterrupted increase in mRNA levels of TGF-β, collagen Ⅰ, and collagen Ⅲ is observed in autogenous vein grafts. This increase may be the major cause of intimal hyperplasia, sclerosis, and even graft failure.

  4. PERSPECTIVE: Dust, fertilization and sources

    Science.gov (United States)

    Remer, Lorraine A.

    2006-11-01

    Aerosols, tiny suspended particles in the atmosphere, play an important role in modifying the Earth's energy balance and are essential for the formation of cloud droplets. Suspended dust particles lifted from the world's arid regions by strong winds contain essential minerals that can be transported great distances and deposited into the ocean or on other continents where productivity is limited by lack of usable minerals [1]. Dust can transport pathogens as well as minerals great distance, contributing to the spread of human and agricultural diseases, and a portion of dust can be attributed to human activity suggesting that dust radiative effects should be included in estimates of anthropogenic climate forcing. The greenish and brownish tints in figure 1 show the wide extent of monthly mean mineral dust transport, as viewed by the MODerate resolution Imaging Spectroradiometer (MODIS) satellite sensor. The monthly mean global aerosol system for February 2006 from the MODIS aboard the Terra satellite Figure 1. The monthly mean global aerosol system for February 2006 from the MODIS aboard the Terra satellite. The brighter the color, the greater the aerosol loading. Red and reddish tints indicate aerosol dominated by small particles created primarily from combustion processes. Green and brownish tints indicate larger particles created from wind-driven processes, usually transported desert dust. Note the bright green band at the southern edge of the Saharan desert, the reddish band it must cross if transported to the southwest and the long brownish transport path as it crosses the Atlantic to South America. Image courtesy of the NASA Earth Observatory (http://earthobservatory.nasa.gov). Even though qualitatively we recognize the extent and importance of dust transport and the role that it plays in fertilizing nutrient-limited regions, there is much that is still unknown. We are just now beginning to quantify the amount of dust that exits one continental region and the

  5. 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 ...

  6. Dust in protoplanetary disks: observations*

    Directory of Open Access Journals (Sweden)

    Waters L.B.F.M.

    2015-01-01

    Full Text Available Solid particles, usually referred to as dust, are a crucial component of interstellar matter and of planet forming disks surrounding young stars. Despite the relatively small mass fraction of ≈1% (in the solar neighborhood of our galaxy; this number may differ substantially in other galaxies that interstellar grains represent of the total mass budget of interstellar matter, dust grains play an important role in the physics and chemistry of interstellar matter. This is because of the opacity dust grains at short (optical, UV wavelengths, and the surface they provide for chemical reactions. In addition, dust grains play a pivotal role in the planet formation process: in the core accretion model of planet formation, the growth of dust grains from the microscopic size range to large, cm-sized or larger grains is the first step in planet formation. Not only the grain size distribution is affected by planet formation. Chemical and physical processes alter the structure and chemical composition of dust grains as they enter the protoplanetary disk and move closer to the forming star. Therefore, a lot can be learned about the way stars and planets are formed by observations of dust in protoplanetary disks. Ideally, one would like to measure the dust mass, the grain size distribution, grain structure (porosity, fluffiness, the chemical composition, and all of these as a function of position in the disk. Fortunately, several observational diagnostics are available to derive constrains on these quantities. In combination with rapidly increasing quality of the data (spatial and spectral resolution, a lot of progress has been made in our understanding of dust evolution in protoplanetary disks. An excellent review of dust evolution in protoplanetary disks can be found in Testi et al. (2014.

  7. Dust-acoustic waves and stability in the permeating dust plasma: II. Power-law distributions

    CERN Document Server

    Gong, Jingyu; Du, Jiulin

    2012-01-01

    The dust-acoustic waves and their stability driven by a flowing dust plasma when it cross through a static (target) dust plasma (the so-called permeating dust plasma) are investigated when the components of the dust plasma obey the power-law q-distributions in nonextensive statistics. The frequency, the growth rate and the stability condition of the dust-acoustic waves are derived under this physical situation, which express the effects of the nonextensivity as well as the flowing dust plasma velocity on the dust-acoustic waves in this dust plasma. The numerical results illustrate some new characteristics of the dust-acoustic waves, which are different from those in the permeating dust plasma when the plasma components are the Maxwellian distribution. In addition, we show that the flowing dust plasma velocity has a significant effect on the dust-acoustic waves in the permeating dust plasma with the power-law q-distribution.

  8. Placement of implants in an ossifying fibroma defect obliterated with demineralized, freeze-dried bone allograft and Plasma-rich growth factor

    Directory of Open Access Journals (Sweden)

    Umashankar Pal

    2012-01-01

    Full Text Available There has been considerable clinical interest in combining the grafts, particularly bone allografts for support for dental implants, soft-tissue support, periodontal maintenance, and ovate pontic formation. The use of demineralized, freeze-dried bone allograft (DFDBA offers certain advantages over other graft materials and can avoid the need for a second-site surgery for autogenous donor bone. The advantages of DFDBA include handling properties, osteoinductivity, membrane tenting, and less susceptibility to migration after placement. This article will review available grafting materials and demonstrate a case of ossifying fibroma of the mandible, which was treated by curettage and hollow cavity filled with DFDBA. Six months follow-up period showed successful graft result and this grafted bone form was utilized for implant supported prosthesis.

  9. E ring dust sources: Implications from Cassini's dust measurements

    Science.gov (United States)

    Spahn, Frank; Albers, Nicole; Hörning, Marcel; Kempf, Sascha; Krivov, Alexander V.; Makuch, Martin; Schmidt, Jürgen; Seiß, Martin; Miodrag Sremčević

    2006-08-01

    The Enceladus flybys of the Cassini spacecraft are changing our understanding of the origin and sustainment of Saturn's E ring. Surprisingly, beyond the widely accepted dust production caused by micrometeoroid impacts onto the atmosphereless satellites (the impactor-ejecta process), geophysical activities have been detected at the south pole of Enceladus, providing an additional, efficient dust source. The dust detector data obtained during the flyby E11 are used to identify the amount of dust produced in the impactor-ejecta process and to improve related modeling [Spahn, F., Schmidt, J., Albers, N., Hörning, M., Makuch, M., Seiß, M., Kempf, S., Srama, R., Dikarev, V.V., Helfert, S., Moragas-Klostermeyer, G., Krivov, A.V., Sremčević, M., Tuzzolino, A., Economou, T., Grün, E., 2006. Cassini dust measurements at Enceladus: implications for Saturn's E ring. Science, in press]. With this, we estimate the impact-generated dust contributions of the other E ring satellites and find significant differences in the dust ejection efficiency by two projectile families - the E ring particles (ERPs) and the interplanetary dust particles (IDPs). Together with the Enceladus south-pole source, the ERP impacts play a crucial role in the inner region, whereas the IDP impacts dominate the particle production in the outer E ring, possibly accounting for its large radial extent. Our results can be verified in future Cassini flybys of the E ring satellites. In this way poorly known parameters of the dust particle production in hypervelocity impacts can be constrained by comparison of the data and theory.

  10. Nostril Base Augmentation Effect of Alveolar Bone Graft

    Directory of Open Access Journals (Sweden)

    Woojin Lee

    2013-09-01

    Full Text Available Background The aims of alveolar bone grafting are closure of the fistula, stabilization ofthe maxillary arch, support for the roots of the teeth adjacent to the cleft on each side.We observed nostril base augmentation in patients with alveolar clefts after alveolar bonegrafting. The purpose of this study was to evaluate the nostril base augmentation effect ofsecondary alveolar bone grafting in patients with unilateral alveolar cleft.Methods Records of 15 children with alveolar clefts who underwent secondary alveolar bonegrafting with autogenous iliac cancellous bone between March of 2011 and May of 2012 werereviewed. Preoperative and postoperative worm’s-eye view photographs and reconstructedthree-dimensional computed tomography (CT scans were used for photogrammetry. Thedepression of the nostril base and thickness of the philtrum on the cleft side were measuredin comparison to the normal side. The depression of the cleft side pyriform aperture wasmeasured in comparison to the normal side on reconstructed three-dimensional CT.Results Significant changes were seen in the nostril base (P=0.005, the philtrum length(P=0.013, and the angle (P=0.006. The CT measurements showed significant changes in thepyriform aperture (P<0.001 and the angle (P<0.001.Conclusions An alveolar bone graft not only fills the gap in the alveolar process but alsoaugments the nostril base after surgery. In this study, only an alveolar bone graft was performedto prevent bias from other procedures. Nostril base augmentation can be achieved byperforming alveolar bone grafts in children, in whom invasive methods are not advised.

  11. 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...

  12. [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.

  13. Sequential Fluorescent Labeling Observation of Maxillary Sinus Augmentation by a Tissue-engineered Bone Complex in Canine Model

    Institute of Scientific and Technical Information of China (English)

    Xin-quan Jiang; Shao-yi Wang; Jun Zhao; Xiu-li Zhang; Zhi-yuan Zhang

    2009-01-01

    Aim To evaluate the effects of maxillary sinus floor elevation by a tissue-engineered bone complex of β-tricalcium phosphate (β-TCP) and autologous osteoblasts in dogs. Methodology Autologous osteoblasts from adult Beagle dogs were cultured in vitro. They were further combined with β-TCP to construct the tissue-engineered bone complex. 12 cases of maxillary sinus floor elevation surgery were made bilaterally in 6 animals and randomly repaired with the following 3 groups of materials: Group A (osteoblasts/β-TCP); Group B (β-TCP); Group C (autogenous bone) (n-4 per group). A polychrome sequential fluorescent labeling was performed post-operatively and the animals were sacrificed 24 weeks after operation for histological observation.Results Our results showed that autologous osteoblasts were successfully expanded and the osteoblastic phenoltypes were confirmed by ALP and Alizarin red staining. The cells could attach and proliferate well on the surface of the β-TCP scaffold. The fluorescent and histological observation showed that the tissue-engineered bone complex had an earlier mineralization and more bone formation inside the scaffold than β-TCP along or even autologous bone. It had also maximally maintained the elevated sinus height than both control groups. Conclusion Porous β-TCP has served as a good scaffold for autologous osteoblasts seeding. The tissue-engineered bone complex with β-TCP and autologous osteoblasts might be a better alternative to autologous bone for the clinical edentulous maxillary sinus augmentation.

  14. Femoral head-neck junction reconstruction, after iatrogenic bone resection.

    Science.gov (United States)

    Guevara-Alvarez, Alberto; Lash, Nicholas; Beck, Martin

    2015-07-01

    Arthroscopic over-resection of the head-neck junction during the treatment of a cam deformity can be a devastating complication and is difficult to treat. Large defects of the femoral head-neck junction (FHNJ) increase the risk of femoral neck fracture and can also affect hip biomechanics. We describe a case of an iatrogenic defect of the FHNJ due to excessive bone resection, and a previously non-described treatment using iliac crest autograft to restore femoral head-neck sphericity and hip joint stability. After protecting the femoral neck with an angled blade plate, the large anterior FHNJ defect was reconstructed using autogenous iliac crest bone graft; sphericity was restored by contouring the graft using spherical templates. Clinical and radiographic follow-up was performed up to 2 years. Results at 2 years showed no residual groin pain and normal range of motion. The Oxford Hip Score was 46/48, rated as excellent. Computed tomography (CT) scanning showed union of bone graft without resorption, and CT arthrogram indicating retained sphericity of the FHNJ without evidence of degenerative changes in the articular surface. This novel surgical technique can be used to restore the structural integrity and contour of the FHNJ that contains a significant anterior defect.

  15. Dust ablation in Pluto's atmosphere

    Science.gov (United States)

    Horanyi, Mihaly; Poppe, Andrew; Sternovsky, Zoltan

    2016-04-01

    Based on measurements by dust detectors onboard the Pioneer 10/11 and New Horizons spacecraft the total production rate of dust particles born in the Edgeworth Kuiper Belt (EKB) has been be estimated to be on the order of 5 ṡ 103 kg/s in the approximate size range of 1 - 10 μm. Dust particles are produced by collisions between EKB objects and their bombardment by both interplanetary and interstellar dust particles. Dust particles of EKB origin, in general, migrate towards the Sun due to Poynting-Robertson drag but their distributions are further sculpted by mean-motion resonances as they first approach the orbit of Neptune and later the other planets, as well as mutual collisions. Subsequently, Jupiter will eject the vast majority of them before they reach the inner solar system. The expected mass influx into Pluto atmosphere is on the order of 200 kg/day, and the arrival speed of the incoming particles is on the order of 3 - 4 km/s. We have followed the ablation history as function of speed and size of dust particles in Pluto's atmosphere, and found that volatile rich particles can fully sublimate due to drag heating and deposit their mass in narrow layers. This deposition might promote the formation of the haze layers observed by the New Horizons spacecraft. This talk will explore the constraints on the composition of the dust particles by comparing the altitude of the deposition layers to the observed haze layers.

  16. 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 ...

  17. Bone lesion biopsy

    Science.gov (United States)

    Bone biopsy; Biopsy - bone ... needle is gently pushed and twisted into the bone. Once the sample is obtained, the needle is ... sample is sent to a lab for examination. Bone biopsy may also be done under general anesthesia ...

  18. Facts about Broken Bones

    Science.gov (United States)

    ... Room? What Happens in the Operating Room? Broken Bones KidsHealth > For Kids > Broken Bones Print A A ... sticking through the skin . What Happens When a Bone Breaks? It hurts to break a bone! It's ...

  19. 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. ...

  20. Broken Bones (For Parents)

    Science.gov (United States)

    ... Feeding Your 1- to 2-Year-Old Broken Bones KidsHealth > For Parents > Broken Bones Print A A ... bone fragments in place. When Will a Broken Bone Heal? Fractures heal at different rates, depending upon ...

  1. Pectoral girdle bones in eurypterygian fishes

    Directory of Open Access Journals (Sweden)

    Yazdan Keivany

    2014-10-01

    Full Text Available Bones of the pectoral girdle skeleton in representatives of 48 genera in 41 families of eurypterygian fishes were studied. The structure and position of the pectoral girdle is relatively stable in eurypterygians. It consists of the extrascapula, posttemporal, supracleithrum, cleithrum, postcleithrum, scapula, coracoid, actinosts, and fin rays. An ectocoracoid is present in some Gasterosteiformes. Most eurypterygians have a posttemporal with distinct dorsal and ventromedial processes. The dorsal process ligamentously articulates with the epioccipital and the ventromedial process with the intercalary when present, and when absent, with the posteroventral margins of the pterotic and exoccipital. In most taxa, the supracleithrum bears a sensory canal and articulates with the posttemporal anteriorly and with the cleithrum posteriorly. The cleithrum is Y-shaped consisting of the anterodorsal, posterodorsal, and ventral rami. Dorsal and ventral postcleithra are present in some Eurypterygii. The scapula articulates with the cleithrum and bears a foramen which is complete or open anteriorly and bordered by the cleithral ventral ramus. Most taxa have four autogenous actinosts that increase in size gradually from the first to the fourth, but in some, the first actinost is fused. The dorsalmost ray is rudimentary in some taxa.

  2. Application of human amniotic mesenchymal cells as an allogeneic transplantation cell source in bone regenerative therapy

    Energy Technology Data Exchange (ETDEWEB)

    Tsuno, Hiroaki [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Yoshida, Toshiko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Nogami, Makiko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Orthopedic Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Koike, Chika; Okabe, Motonori [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Noto, Zenko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Arai, Naoya; Noguchi, Makoto [Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Nikaido, Toshio, E-mail: tnikaido@med.u-toyama.ac.jp [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan)

    2012-12-01

    Autogenous mesenchymal stem cells (MSCs) have therapeutic applications in bone regenerative therapy due to their pluripotency. However, the ability of MSCs to proliferate and differentiate varies between donors. Furthermore, alternative sources of MSCs are required for patients with contraindications to autogenous cell therapy. The aim of this study was to evaluate the potential of mesenchymal cells from the human amniotic membrane (HAM) as a source of cells for allogeneic transplantation in bone regenerative therapy. Cells that retained a proliferative capacity of more than 50 population doubling level were distinguished from other HAM cells as HAM{alpha} cells and induced to osteogenic status-their in vivo osteogenesis was subsequently investigated in rats. It was found that HAM{alpha} cells were spindle shaped and were positive for MSC markers and negative for hematopoietic stem cell markers. Alkaline phosphatase activity and calcium deposition increased with osteogenic status of HAM{alpha} cells. The expression of osteocalcin mRNA was increased in HAM{alpha} cells cultured on calcium phosphate scaffolds. Moreover, xenografted HAM{alpha} cells remained viable and produced extracellular matrix for several weeks. Thus, this study suggests that human amniotic mesenchymal cells possess osteogenic differentiation potential and could be applied to allogeneic transplantation in bone regenerative therapy. - Highlights: Black-Right-Pointing-Pointer Human amniotic mesenchymal cells include cells (HAM{alpha} cells) that have the properties of MSCs. Black-Right-Pointing-Pointer HAM{alpha} cells have excellent osteogenic differentiation potential. Black-Right-Pointing-Pointer Osteogenic differentiation ability of HAM{alpha} was amplified by calcium phosphate scaffolds. Black-Right-Pointing-Pointer HAM{alpha} cells can be applicable to allogeneic cell transplantation in bone regenerative therapy.

  3. Bone marrow combined with dental bud cells promotes tooth regeneration in miniature pig model.

    Science.gov (United States)

    Kuo, Tzong-Fu; Lin, Hsin-Chi; Yang, Kai-Chiang; Lin, Feng-Huei; Chen, Min-Huey; Wu, Chang-Chin; Chang, Hao-Hueng

    2011-02-01

    Growth factors and morphogens secreted by bone marrow mesenchymal stem cells (BMSCs) of bone marrow fluid may promote tooth regeneration. Accordingly, a tissue engineering approach was utilized to develop an economical strategy for obtaining the growth factors and morphogens from BMSCs. Unerupted second molar tooth buds harvested from miniature pigs were cultured in vitro to obtain dental bud cells (DBCs). Bone marrow fluid, which contains BMSCs, was collected from the porcine mandible before operation. DBCs suspended in bone marrow fluid were seeded into a gelatin/chondoitin-6-sulfate/hyaluronan tri-copolymer scaffold (GCHT scaffold). The DBCs/bone marrow fluid/GCHT scaffold was autografted into the original alveolar sockets of the pigs. Radiographic and histological examinations were applied to identify the structure of regenerated tooth at 40 weeks postimplantation. The present results showed that one pig developed a complete tooth with crown, root, pulp, enamel, dentin, odontoblast, cementum, blood vessel, and periodontal ligament in indiscriminate shape. Three animals had an unerupted tooth that expressed dentin matrix protein-1, vascular endothelial growth factor, and osteopontin; and two other pigs also had dental-like structure with dentin tubules. This study reveals that DBCs adding bone marrow fluid and a suitable scaffold can promote the tooth regeneration in autogenic cell transplantation.

  4. Dust Storms: Why Are Dust Storms a Concern?

    Science.gov (United States)

    ... Radon Solvents Styrene Sulfur Dioxide Toluene Uranium Volatile Organic Compounds (VOCs) For Educators Introduction Tox Town-Based Curriculum Units / Science Club Careers in Environmental Health, Chemistry, and Toxicology More Resources Dust Storms en español ...

  5. The efficacy of hydrothermally obtained carbonated hydroxyapatite in healing alveolar bone defects in rats with or without corticosteroid treatment

    Directory of Open Access Journals (Sweden)

    Marković Dejan

    2014-01-01

    Full Text Available Background/Aim. Autogenous bone grafting has been the gold standard in clinical cases when bone grafts are required for bone defects in dentistry. The study was undertaken to evaluate multilevel designed carbonated hydroxyapatite (CHA obtained by hydrothermal method, as a bone substitute in healing bone defects with or without corticosteroid treatment in rats as assessed by histopathologic methods. Methods. Bone defects were created in the alveolar bone by teeth extraction in 12 rats. The animals were initially divided into two groups. The experimental group was pretreated with corticosteroids: methylprednisolone and dexamethasone, intramuscularly, while the control group was without therapy. Posterior teeth extraction had been performed after the corticosteroid therapy. The extraction defects were fulfilled with hydroxyapatite with bimodal particle sizes in the range of 50-250 μm and the sample from postextocactional defect of the alveolar bone was analyzed pathohystologically. Results. The histopatological investigations confirmed the biologic properties of the applied material. The evident growth of new bone in the alveolar ridge was clearly noticed in both groups of rats. Carbonated HA obtained by hydrothermal method promoted bone formation in the preformed defects, confirming its efficacy for usage in bone defects. Complete resorption of the material’s particles took place after 25 weeks. Conclusion. Hydroxyapatite completely meets the clinical requirements for a bone substitute material. Due to its microstructure, complete resorption took place during the observation period of the study. Corticosteroid treatment did not significantly affect new bone formation in the region of postextractional defects. [Projekat Ministarstva nauke Republike Srbije, br. 172026

  6. Design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite as a potential bone graft substitute material

    Science.gov (United States)

    Florschutz, Anthony Vatroslav

    Utilization of bone grafts for the treatment of skeletal pathology is a common practice in orthopaedic, craniomaxillofacial, dental, and plastic surgery. Autogenous bone graft is the established archetype but has disadvantages including donor site morbidity, limited supply, and prolonging operative time. In order to avoid these and other issues, bone graft substitute materials are becoming increasingly prevalent among surgeons for reconstructing skeletal defects and arthrodesis applications. Bone graft substitutes are biomaterials, biologics, and guided tissue/bone regenerative devices that can be used alone or in combinations as supplements or alternatives to autogenous bone graft. There is a growing interest and trend to specialize graft substitutes for specific indications and although there is good rationale for this indication-specific approach, the development and utility of a more universal bone graft substitute may provide a better answer for patients and surgeons. The aim of the present research focuses on the design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite composites for potential use as a bone graft substitutes. After initial establishment of rational material design, gelatinhydroxyapatite scaffolds were fabricated with different gelatin:hydroxyapatite ratios and crosslinking concentrations. The synthesized scaffolds were subsequently evaluated on the basis of their swelling behavior, porosity, density, percent composition, mechanical properties, and morphology and further assessed with respect to cell-biomaterial interaction and biomineralization in vitro. Although none of the materials achieved mechanical properties suitable for structural graft applications, a reproducible material design and synthesis was achieved with properties recognized to facilitate bone formation. Select scaffold formulations as well as a subset of scaffolds loaded with recombinant human bone morphogenetic protein-2 were

  7. 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...

  8. [Causation, prevention and treatment of dust explosion].

    Science.gov (United States)

    Dong, Maolong; Jia, Wenbin; Wang, Hongtao; Han, Fei; Li, Xiao-Qiang; Hu, Dahai

    2014-10-01

    With the development of industrial technology, dust explosion accidents have increased, causing serious losses of people's lives and property. With the development of economy, we should lay further emphasis on causation, prevention, and treatment of dust explosion. This article summarizes the background, mechanism, prevention, and treatment of dust explosion, which may provide some professional knowledge and reference for the treatment of dust explosion.

  9. A numerical study on dust devils with implications to global dust budget estimates

    Science.gov (United States)

    The estimates of the contribution of dust devils (DDs) to the global dust budget have large uncertainties because the dust emission mechanisms in DDs are not yet well understood. In this study, a large-eddy simulation model coupled with a dust scheme is used to investigate DD dust entrainment. DDs a...

  10. Metals and dust in high redshift AGNs

    CERN Document Server

    Maiolino, R; Marconi, A; Schneider, R; Bianchi, S; Pedani, M; Pipino, A; Matteucci, F; Cox, P; Caselli, P

    2006-01-01

    We summarize some recent results on the metallicity and dust properties of Active Galactic Nuclei (AGN) at high redshift (110). The properties of dust in high-z QSOs are discussed within the context of the dust production mechanisms in the early universe. The dust extinction curve is observed to evolve beyond z>4, and by z~6 it is well described by the properties expected for dust produced by SNe, suggesting that the latter is the main mechanism of dust production in the early universe. We also show that the huge dust masses observed in distant QSOs can be accounted for by SN dust within the observational constraints currently available. Finally, we show that QSO winds, which have been proposed as an alternative mechanism of dust production, may also contribute significantly to the total dust budget at high redshift.

  11. Wormhole shadows in rotating dust

    Science.gov (United States)

    Ohgami, Takayuki; Sakai, Nobuyuki

    2016-09-01

    As an extension of our previous work, which investigated the shadows of the Ellis wormhole surrounded by nonrotating dust, in this paper we study wormhole shadows in a rotating dust flow. First, we derive steady-state solutions of slowly rotating dust surrounding the wormhole by solving relativistic Euler equations. Solving null geodesic equations and radiation transfer equations, we investigate the images of the wormhole surrounded by dust for the above steady-state solutions. Because the Ellis wormhole spacetime possesses unstable circular orbits of photons, a bright ring appears in the image, just as in Schwarzschild spacetime. The bright ring looks distorted due to rotation. Aside from the bright ring, there appear weakly luminous complex patterns by the emission from the other side of the throat. These structure could be detected by high-resolution very-long-baseline-interferometry observations in the near future.

  12. Loess and Eolian Dust Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past environment derived from Loess and Eolian dust (silt-sized material deposited on the Earth surface by the surface winds. Parameter keywords describe...

  13. Dust Evolution in Protoplanetary Disks

    CERN Document Server

    Testi, Leonardo; Ricci, Luca; Andrews, Sean; Blum, Juergen; Carpenter, John; Dominik, Carsten; Isella, Andrea; Natta, Antonella; Williams, Jonathan; Wilner, David

    2014-01-01

    (abridged) In the core accretion scenario for the formation of planetary rocky cores, the first step toward planet formation is the growth of dust grains into larger and larger aggregates and eventually planetesimals. Although dust grains are thought to grow from the submicron sizes typical of interstellar dust to micron size particles in the dense regions of molecular clouds and cores, the growth from micron size particles to pebbles and kilometre size bodies must occur in protoplanetary disks. This step in the formation of planetary systems is the last stage of solids evolution that can be observed directly in young extrasolar systems. In this chapter we review the constraints on the physics of grain-grain collisions as they have emerged from laboratory experiments and numerical computations. We then review the current theoretical understanding of the global processes governing the evolution of solids in protoplanetary disks, including dust settling, growth, and radial transport. The predicted observational...

  14. Surface System Dust Mitigation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed effort will perform a detailed examination of dust mitigation and tolerance strategies for connections and mechanisms to be employed on the lunar...

  15. Autogenic versus allogenic controls on the evolution of a coupled fluvial megafan-mountainous catchment system: numerical modelling and comparison with the Lannemezan megafan system (northern Pyrenees, France)

    Science.gov (United States)

    Mouchené, Margaux; van der Beek, Peter; Carretier, Sébastien; Mouthereau, Frédéric

    2017-02-01

    Alluvial megafans are sensitive recorders of landscape evolution, controlled by both autogenic processes and allogenic forcing, and they are influenced by the coupled dynamics of the fan with its mountainous catchment. The Lannemezan megafan in the northern Pyrenean foreland was abandoned by its mountainous feeder stream during the Quaternary and subsequently incised, leaving a flight of alluvial terraces along the stream network. We use numerical models to explore the relative roles of autogenic processes and external forcing in the building, abandonment and incision of a foreland megafan, and we compare the results with the inferred evolution of the Lannemezan megafan. Autogenic processes are sufficient to explain the building of a megafan and the long-term entrenchment of its feeding river on time and space scales that match the Lannemezan setting. Climate, through temporal variations in precipitation rate, may have played a role in the episodic pattern of incision on a shorter timescale. In contrast, base-level changes, tectonic activity in the mountain range or tilting of the foreland through flexural isostatic rebound do not appear to have played a role in the abandonment of the megafan.

  16. The Long-Term Results of Frontalis Suspension Using Autogenous Fascia Lata in Children with Congenital Ptosis under 3 Years Old

    Directory of Open Access Journals (Sweden)

    Lale Kozer Bilgin

    2010-01-01

    Full Text Available Purpose. To describe the long-term results of frontalis suspension using autogenous fascia lata in children with congenital ptosis under 3 years old. Methods. Forty three-eyes of 35 patients were enrolled in the study. Frontalis suspension using autogenous fascia lata was performed in all patients. The postoperative eyelid level, ptosis recurrence, visual acuity, and cosmetic results were evaluated. Results. The mean age of the patients was 16.8±9 months (7–36 months. The mean follow-up time was 52.8±15 months (14–95 months. All patients had good (ptosis <2 mm or moderate (2-3 mm ptosis eyelid level after the operation. All patients achieved satisfactory cosmetic results. Succesfull harvesting was performed in all cases and no additional materials or surgical manipulation were needed during the surgery. Conclusion. Frontalis suspension using autogenous fascia lata can be used in children under 3 years old without harvesting problems. Surgical experience and good knowledge of anatomy are important factors for successful results after the surgery.

  17. Dust vortex flows in plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Shukla, P.K

    2002-12-30

    Coherent nonlinear structures in the form of dust vortex flows have been observed in unmagnetized laboratory dusty plasmas. Our objective here is show that the dynamics of such dust vortices is governed by a modified Navier-Stokes equation (MNSE) and that the stationary solutions of the MNSE can be represented as monopolar as well as a row of identical Stuart and a row of counter-rotating vortices.

  18. Dust Evolution in Protoplanetary Disks

    Science.gov (United States)

    Testi, L.; Birnstiel, T.; Ricci, L.; Andrews, S.; Blum, J.; Carpenter, J.; Dominik, C.; Isella, A.; Natta, A.; Williams, J. P.; Wilner, D. J.

    In the core-accretion scenario for the formation of planetary rocky cores, the first step toward planet formation is the growth of dust grains into larger and larger aggregates and eventually planetesimals. Although dust grains are thought to grow up to micrometer-sized particles in the dense regions of molecular clouds, the growth to pebbles and kilometer-sized bodies must occur at the high densities within protoplanetary disks. This critical step is the last stage of solids evolution that can be observed directly in extrasolar systems before the appearance of large planetary-sized bodies. In this chapter we review the constraints on the physics of grain-grain collisions as they have emerged from laboratory experiments and numerical computations. We then review the current theoretical understanding of the global processes governing the evolution of solids in protoplanetary disks, including dust settling, growth, and radial transport. The predicted observational signatures of these processes are summarized. We briefly discuss grain growth in molecular cloud cores and in collapsing envelopes of protostars, as these likely provide the initial conditions for the dust in protoplanetary disks. We then review the observational constraints on grain growth in disks from millimeter surveys, as well as the very recent evidence for radial variations of the dust properties in disks. We also include a brief discussion on the small end of the grain size distribution and dust settling as derived from optical, near-, and mid-infrared observations. Results are discussed in the context of global dust-evolution models; in particular, we focus on the emerging evidence for a very efficient early growth of grains and the radial distribution of maximum grain sizes as the result of growth barriers. We also highlight the limits of the current models of dust evolution in disks, including the need to slow the radial drift of grains to overcome the migration/fragmentation barrier.

  19. Uranium mill ore dust characterization

    Energy Technology Data Exchange (ETDEWEB)

    Knuth, R.H.; George, A.C.

    1980-11-01

    Cascade impactor and general air ore dust measurements were taken in a uranium processing mill in order to characterize the airborne activity, the degree of equilibrium, the particle size distribution and the respirable fraction for the /sup 238/U chain nuclides. The sampling locations were selected to limit the possibility of cross contamination by airborne dusts originating in different process areas of the mill. The reliability of the modified impactor and measurement techniques was ascertained by duplicate sampling. The results reveal no significant deviation from secular equilibrium in both airborne and bulk ore samples for the /sup 234/U and /sup 230/Th nuclides. In total airborne dust measurements, the /sup 226/Ra and /sup 210/Pb nuclides were found to be depleted by 20 and 25%, respectively. Bulk ore samples showed depletions of 10% for the /sup 226/Ra and /sup 210/Pb nuclides. Impactor samples show disequilibrium of /sup 226/Ra as high as +-50% for different size fractions. In these samples the /sup 226/Ra ratio was generally found to increase as particle size decreased. Activity median aerodynamic diameters of the airborne dusts ranged from 5 to 30 ..mu..m with a median diameter of 11 ..mu..m. The maximum respirable fraction for the ore dusts, based on the proposed International Commission on Radiological Protection's (ICRP) definition of pulmonary deposition, was < 15% of the total airborne concentration. Ore dust parameters calculated for impactor duplicate samples were found to be in excellent agreement.

  20. Dust in the Interplanetary Medium

    CERN Document Server

    Mann, Ingrid; Meyer-Vernet, Nicole; Zaslavsky, Arnaud; Lamy, Herve

    2010-01-01

    The mass density of dust particles that form from asteroids and comets in the interplanetary medium of the solar system is, near 1 AU, comparable to the mass density of the solar wind. It is mainly contained in particles of micrometer size and larger. Dust and larger objects are destroyed by collisions and sublimation and hence feed heavy ions into the solar wind and the solar corona. Small dust particles are present in large number and as a result of their large charge to mass ratio deflected by electromagnetic forces in the solar wind. For nano dust particles of sizes 1 - 10 nm, recent calculations show trapping near the Sun and outside from about 0.15 AU ejection with velocities close to solar wind velocity. The fluxes of ejected nano dust are detected near 1AU with the plasma wave instrument onboard the STEREO spacecraft. Though such electric signals have been observed during dust impacts before, the interpretation depends on several different parameters and data analysis is still in progress.

  1. The Cosmic DUNE dust astronomy mission

    Science.gov (United States)

    Grun, E.; Srama, R.; Cosmic Dune Team

    A dust astronomy mission aims at the simultaneous measurement of the origin and the chemical composition of individual dust grains in space. Interstellar dust traversing the solar system constitutes the galactic solid phase of matter from which stars and planetary systems form. Interplanetary dust, from comets and asteroids, represents remnant material from bodies at different stages of early solar system evolution. Thus, studies of interstellar and interplanetary dust with Cosmic DUNE (Cosmic Dust Near Earth) will provide a comparison between the composition of the interstellar medium and primitive planetary objects. Cosmic DUNE will prepare the way for effective collection in near-Earth space of interstellar and interplanetary dust for subsequent return to Earth and analysis in laboratories. Cosmic DUNE establishes the next logical step beyond NASA's Stardust mission, with four major advancements in cosmic dust research: (1) Analysis of the elemental and isotopic composition of individual cosmic dust grains, (2) determination of the size distribution of interstellar dust, (3) characterization of the interstellar dust flow through the planetary system, and (4) analysis of interplanetary dust of cometary and asteroidal origin. This mission goal will be reached with novel dust instrumentation. A dust telescope trajectory sensor has been developed which is capable of obtaining precision trajectories of sub-micron sized particles in space. A new high mass resolution dust analyzer of 0.1m2 impact area can cope with the low fluxes expected in interplanetary space. Cosmic DUNE will be proposed to ESA in response to its upcoming call for mission ideas.

  2. Negative Autogenous Control of the Master Type III Secretion System Regulator HrpL in Pseudomonas syringae

    Science.gov (United States)

    Waite, Christopher; Schumacher, Jörg; Jovanovic, Milija; Bennett, Mark

    2017-01-01

    ABSTRACT   The type III secretion system (T3SS) is a principal virulence determinant of the model bacterial plant pathogen Pseudomonas syringae. T3SS effector proteins inhibit plant defense signaling pathways in susceptible hosts and elicit evolved immunity in resistant plants. The extracytoplasmic function sigma factor HrpL coordinates the expression of most T3SS genes. Transcription of hrpL is dependent on sigma-54 and the codependent enhancer binding proteins HrpR and HrpS for hrpL promoter activation. hrpL is oriented adjacently to and divergently from the HrpL-dependent gene hrpJ, sharing an intergenic upstream regulatory region. We show that association of the RNA polymerase (RNAP)-HrpL complex with the hrpJ promoter element imposes negative autogenous control on hrpL transcription in P. syringae pv. tomato DC3000. The hrpL promoter was upregulated in a ΔhrpL mutant and was repressed by plasmid-borne hrpL. In a minimal Escherichia coli background, the activity of HrpL was sufficient to achieve repression of reconstituted hrpL transcription. This repression was relieved if both the HrpL DNA-binding function and the hrp-box sequence of the hrpJ promoter were compromised, implying dependence upon the hrpJ promoter. DNA-bound RNAP-HrpL entirely occluded the HrpRS and partially occluded the integration host factor (IHF) recognition elements of the hrpL promoter in vitro, implicating inhibition of DNA binding by these factors as a cause of negative autogenous control. A modest increase in the HrpL concentration caused hypersecretion of the HrpA1 pilus protein but intracellular accumulation of later T3SS substrates. We argue that negative feedback on HrpL activity fine-tunes expression of the T3SS regulon to minimize the elicitation of plant defenses. PMID:28119474

  3. Avoiding graft-tunnel length mismatch in anterior cruciate ligament reconstruction: the single-bone plug technique.

    Science.gov (United States)

    Grawe, Brian; Smerina, Amber; Allen, Answorth

    2014-06-01

    Anterior cruciate ligament reconstruction, using autogenous bone-patellar tendon-bone (BTB) as a graft material, is commonly performed in the setting of anterior cruciate ligament insufficiency. Although bone-patellar tendon-bone autograft has an extensive track record, showing excellent clinical results, donor-site morbidity and graft-tunnel mismatch can still be problematic for a subset of patients. In the setting of a tendon graft that is too long, adequate interference screw fixation cannot be obtained, typically resulting in a tibial-sided bone plug that achieves less than 15 to 20 mm of bone in the distal tibial tunnel. We present an easy and effective technique for avoiding the graft-tunnel mismatch problems that commonly occur in patients who have an excessively long patellar tendons. This technique involves a simple preoperative planning algorithm that ultimately results in a single tibial-sided plug harvest. Bony interference fixation is then obtained on the femoral side and soft-tissue fixation on the tibial side. This technique allows for satisfactory graft fixation while avoiding the donor-site morbidity associated with patellar bone plug harvest.

  4. Estimation of high altitude Martian dust parameters

    Science.gov (United States)

    Pabari, Jayesh; Bhalodi, Pinali

    2016-07-01

    Dust devils are known to occur near the Martian surface mostly during the mid of Southern hemisphere summer and they play vital role in deciding background dust opacity in the atmosphere. The second source of high altitude Martian dust could be due to the secondary ejecta caused by impacts on Martian Moons, Phobos and Deimos. Also, the surfaces of the Moons are charged positively due to ultraviolet rays from the Sun and negatively due to space plasma currents. Such surface charging may cause fine grains to be levitated, which can easily escape the Moons. It is expected that the escaping dust form dust rings within the orbits of the Moons and therefore also around the Mars. One more possible source of high altitude Martian dust is interplanetary in nature. Due to continuous supply of the dust from various sources and also due to a kind of feedback mechanism existing between the ring or tori and the sources, the dust rings or tori can sustain over a period of time. Recently, very high altitude dust at about 1000 km has been found by MAVEN mission and it is expected that the dust may be concentrated at about 150 to 500 km. However, it is mystery how dust has reached to such high altitudes. Estimation of dust parameters before-hand is necessary to design an instrument for the detection of high altitude Martian dust from a future orbiter. In this work, we have studied the dust supply rate responsible primarily for the formation of dust ring or tori, the life time of dust particles around the Mars, the dust number density as well as the effect of solar radiation pressure and Martian oblateness on dust dynamics. The results presented in this paper may be useful to space scientists for understanding the scenario and designing an orbiter based instrument to measure the dust surrounding the Mars for solving the mystery. The further work is underway.

  5. Circumplanetary dust dynamics : application to Martian dust tori and Enceladus dust plumes

    OpenAIRE

    Makuch, Martin

    2007-01-01

    Our Solar system contains a large amount of dust, containing valuable information about our close cosmic environment. If created in a planet's system, the particles stay predominantly in its vicinity and can form extended dust envelopes, tori or rings around them. A fascinating example of these complexes are Saturnian rings containing a wide range of particles sizes from house-size objects in the main rings up to micron-sized grains constituting the E ring. Other example are ring systems in g...

  6. Bone-Forming Capabilities of a Newly Developed NanoHA Composite Alloplast Infused with Collagen: A Pilot Study in the Sheep Mandible

    Directory of Open Access Journals (Sweden)

    Charles Marin

    2013-01-01

    Full Text Available Lateral or vertical bone augmentation has always been a challenge, since the site is exposed to constant pressure from the soft tissue, and blood supply only exists from the donor site. Although, for such clinical cases, onlay grafting with autogenous bone is commonly selected, the invasiveness of the secondary surgical site and the relatively fast resorption rate have been reported as a drawback, which motivated the investigation of alternative approaches. This study evaluated the bone-forming capability of a novel nanoHA alloplast infused with collagen graft material made from biodegradable polylactic acid/polyglycolic acid versus a control graft material with the same synthesized alloplast without the nanoHA component and collagen infiltration. The status of newly formed bone and the resorption of the graft material were evaluated at 6 weeks in vivo histologically and three dimensionally by means of 3D microcomputed tomography. The histologic observation showed that newly formed bone ingrowth and internal resorption of the block were observed for the experimental blocks, whereas for the control blocks less bone ingrowth occurred along with lower resorption rate of the block material. The three-dimensional observation indicated that the experimental block maintained the external geometry, but at the same time successfully altered the graft material into bone. It is suggested that the combination of numerous factors contributed to the bone ingrowth and the novel development could be an alternative bone grafting choice.

  7. Particle Lifting Processes in Dust Devils

    Science.gov (United States)

    Neakrase, L. D. V.; Balme, M. R.; Esposito, F.; Kelling, T.; Klose, M.; Kok, J. F.; Marticorena, B.; Merrison, J.; Patel, M.; Wurm, G.

    2016-10-01

    Particle lifting in dust devils on both Earth and Mars has been studied from many different perspectives, including how dust devils could influence the dust cycles of both planets. Here we review our current understanding of particle entrainment by dust devils by examining results from field observations on Earth and Mars, laboratory experiments (at terrestrial ambient and Mars-analog conditions), and analytical modeling. By combining insights obtained from these three methodologies, we provide a detailed overview on interactions between particle lifting processes due to mechanical, thermal, electrodynamical and pressure effects, and how these processes apply to dust devils on Earth and Mars. Experiments and observations have shown dust devils to be effective lifters of dust given the proper conditions on Earth and Mars. However, dust devil studies have yet to determine the individual roles of each of the component processes acting at any given time in dust devils.

  8. Elemental tracers for Chinese source dust

    Institute of Scientific and Technical Information of China (English)

    张小曳; 张光宇; 朱光华; 张德二; 安芷生; 陈拓; 黄湘萍

    1996-01-01

    The mass-particle size distributions of 10 dust-carrying elements in aerosol particles were determined tor 12 sites in desert regions of northern China. The desert dust is proved to he of origin of eolian loess deposited on the Loess Plateau. Their transport to the loess was mainly attributable to the non-dust storm processes under the interglacial climate condition. The impact ot" dust storm on the accumulation of the loess increased in the glacial stage. On the basis of the signatures of 4 dust elements (Al. Fe, Mg and Sc). Chinese dust is believed to have 3 major desert sources (northwestern deserts, northern high dust deserts and northern low dust deserts). With a chemical element balance model, an elemental tracer system is established to proportion the export of China-source dust.

  9. 2002 Kuiper prize lecture: Dust Astronomy

    Science.gov (United States)

    Grün, Eberhard; Srama, Ralf; Krüger, Harald; Kempf, Sascha; Dikarev, Valeri; Helfert, Stefan; Moragas-Klostermeyer, Georg

    2005-03-01

    Dust particles, like photons, carry information from remote sites in space and time. From knowledge of the dust particles' birthplace and their bulk properties, we can learn about the remote environment out of which the particles were formed. This approach is called "Dust Astronomy" which is carried out by means of a dust telescope on a Dust Observatory in space. Targets for a dust telescope are the local interstellar medium and nearby star forming regions, as well as comets and asteroids. Dust from interstellar and interplanetary sources is distinguished by accurately sensing their trajectories. Trajectory sensors may use the electric charge signals that are induced when charged grains fly through the detector. Modern in-situ dust impact detectors are capable of providing mass, speed, physical and chemical information of dust grains in space. A Dust Observatory mission is feasible with state-of-the-art technology. It will (1) provide the distinction between interstellar dust and interplanetary dust of cometary and asteroidal origin, (2) determine the elemental composition of impacting dust particles, and (3) monitor the fluxes of various dust components as a function of direction and particle masses.

  10. Saliva amylase as a measure of sympathetic change elicited by autogenic training in patients with functional somatic syndromes.

    Science.gov (United States)

    Kiba, Tadashi; Kanbara, Kenji; Ban, Ikumi; Kato, Fumie; Kawashima, Sadanobu; Saka, Yukie; Yamamoto, Kazumi; Nishiyama, Junji; Mizuno, Yasuyuki; Abe, Tetsuya; Fukunaga, Mikihiko

    2015-12-01

    The aim of this study was to discuss the effect of autogenic training (AT) on patients with functional somatic syndrome (FSS) using salivary amylase, the skin temperature of the finger, subjective severity of symptoms, and psychological characteristics as measures. We assessed 20 patients with FSS and 23 healthy controls before and after AT. Baseline levels of salivary amylase prior to an AT session were significantly higher in the FSS group than in the control group. However, this difference was not significant after AT. The skin temperature of the finger increased after AT in both the FSS and control groups. AT contributed to the improvement of somatic symptoms in patients with FSS. Our results regarding psychological characteristics suggest that mood disturbances are deeply involved in the pathology of FSS. Individuals with FSS exhibited elevated levels of sympathetic activity compared with healthy controls. Our data indicates that AT eased dysregulation of the autonomic nervous system in patients with FSS. Thus, salivary amylase may be a useful index of change induced by AT in patients with FSS.

  11. Parametric Assessment of Stress Development and Cracking in Internally Cured Restrained Mortars Experiencing Autogenous Deformations and Thermal Loading

    Directory of Open Access Journals (Sweden)

    Kambiz Raoufi

    2011-01-01

    Full Text Available A finite element model is used to examine how the properties of cementitious mortar are related to the stress development in the dual ring test. The results of this investigation are used to explain the thermal cracking behavior of mixtures containing prewetted lightweight aggregates (LWA by quantifying the contribution of several material properties individually. In addition to the beneficial effects of using the LWA as an internal curing agent to reduce the autogenous shrinkage of concrete, the LWA also helps to reduce the potential for thermal cracking due to a lower elastic modulus and increased stress relaxation. The rate of stress development, age of cracking, and magnitude of the temperature drop necessary to induce cracking in a dual ring specimen are dependent on a variety of factors, including the coefficient of thermal expansion of both the cementitious mortar and the restraining rings, elastic modulus of the mortar, creep effect of the mortar, and rate of thermal loading. Depending on the rate of cooling, cracking may or may not occur. The slowest rate of cooling (2.5∘C/h minimizes the effects of creep while cooling rates faster than 8∘C/h can produce a thermal gradient through the mortar cross-section that needs to be considered.

  12. Urethral Reconstruction Using Mesothelial Cell-Seeded Autogenous Granulation Tissue Tube: An Experimental Study in Male Rabbits

    Science.gov (United States)

    Jiang, Shiwei; Xu, Zhonghua; Zhao, Yuanyuan; Yan, Lei; Zhou, Zunlin

    2017-01-01

    Objective. This study was to evaluate the utility of the compound graft for tubularized urethroplasty by seeding mesothelial cells onto autogenous granulation tissue. Methods. Silastic tubes were implanted subcutaneously in 18 male rabbits, of which nine underwent omentum biopsies simultaneously for in vitro expansion of mesothelial cells. The granulation tissue covering the tubes was harvested 2 weeks after operation. Mesothelial cells were seeded onto and cocultured with the tissue for 7 days. A pendulous urethral segment of 1.5 cm was totally excised. Urethroplasty was performed with mesothelial cell-seeded tissue tubes in an end-to-end fashion in nine rabbits and with unseeded grafts in others as controls. Serial urethrograms were performed at 1, 2, and 6 months postoperatively. Meanwhile, the neourethra was harvested and analyzed grossly and histologically. Results. Urethrograms showed cell-seeded grafts maintained wide at each time point, while strictures formation was found in unseeded grafts. Histologically, layers of urothelium surrounded by increasingly organized smooth muscles were observed in seeded grafts. In contrast, myofibroblasts accumulation and extensive scarring occurred in unseeded grafts. Conclusions. Mesothelial cell-seeded granulation tissue tube can be successfully used for tubularized urethroplasty in male rabbits.

  13. The effects of autogenic-feedback training on motion sickness severity and heart rate variability in astronauts

    Science.gov (United States)

    Toscano, William B.; Cowings, Patricia S.

    1994-01-01

    Space motion sickness (SMS) affects 50 percent of all people during early days of spaceflight. This study describes the results of two Shuttle flight experiments in which autogenic-feedback training (AFT), a physiological conditioning method, was tested as a treatment for this disorder. Of the six who were designated as flight subjects (two women and four men), three were given treatment and three served as controls (i.e., no AFT). Treatment subjects were given 6 hours of preflight AFT. Preflight results showed that AFT produced a significant increase in tolerance to rotating chair motion sickness tests. Further, this increased tolerance was associated with changes in specific physiological responses and reports of reduced malaise. Flight results showed that two of the three control subjects experienced repeated vomiting on the first mission day, while one subject experienced only moderate malaise. Of the three treatment subjects, one experienced mild discomfort, one moderate discomfort, and one severe motion sickness. Only the three control subjects took medication for symptom suppression. Measures of cardiac function reflective of vagal control were shown to be affected especially strongly on the first day of space flight. AFT given for control of heart rate, respiration, and other autonomic activity influenced both the vagal control measures and SMS. These data suggest that AFT may be an effective treatment for space motion sickness; however, this cannot be demonstrated conclusively with the small number of subjects described.

  14. Dating of cremated bones

    NARCIS (Netherlands)

    Lanting, JN; Aerts-Bijma, AT; van der Plicht, J; Boaretto, E.; Carmi, I.

    2001-01-01

    When dating unburnt bone, bone collagen, the organic fraction of the bone, is used. Collagen does not survive the heat of the cremation pyre, so dating of cremated bone has been considered impossible. Structural carbonate in the mineral fraction of the bone, however, survives the cremation process.

  15. The global atmospheric loading of dust aerosols

    Science.gov (United States)

    Kok, J. F.; Ridley, D. A.; Haustein, K.; Miller, R. L.; Zhao, C.

    2015-12-01

    Mineral dust is one of the most ubiquitous aerosols in the atmosphere, with important effects on human health and the climate system. But despite its importance, the global atmospheric loading of dust has remained uncertain, with model results spanning about a factor of five. Here we constrain the particle size-resolved atmospheric dust loading and global emission rate, using a novel theoretical framework that uses experimental constraints on the optical properties and size distribution of dust to eliminate climate model errors due to assumed dust properties. We find that most climate models underestimate the global atmospheric loading and emission rate of dust aerosols.

  16. Dust characterization in FTU tokamak

    Energy Technology Data Exchange (ETDEWEB)

    De Angeli, M., E-mail: deangeli@ifp.cnr.it [Istituto di Fisica del Plasma – Consiglio Nazionale delle Ricerche, Milan (Italy); Maddaluno, G. [ENEA Unità Tecnica Fusione, C.R. ENEA Frascati, CP65, 00044 Frascati (Italy); Laguardia, L. [Istituto di Fisica del Plasma – Consiglio Nazionale delle Ricerche, Milan (Italy); Ripamonti, D. [Istituto per l’Energetica e le Interfasi – Consiglio Nazionale delle Ricerche, Milan (Italy); Perelli Cippo, E. [Istituto di Fisica del Plasma – Consiglio Nazionale delle Ricerche, Milan (Italy); Apicella, M.L. [ENEA Unità Tecnica Fusione, C.R. ENEA Frascati, CP65, 00044 Frascati (Italy); Conti, C. [Istituto per la Conservazione e la Valorizzazione dei Beni Culturali – CNR, Milan (Italy); Giacomi, G. [ENEA Unità Tecnica Fusione, C.R. ENEA Frascati, CP65, 00044 Frascati (Italy); Grosso, G. [Istituto di Fisica del Plasma – Consiglio Nazionale delle Ricerche, Milan (Italy)

    2015-08-15

    Dust present in the vessel of FTU has been collected and analysed. Being FTU a device with full metal plasma facing components for the whole life and equipped with a liquid lithium limiter (LLL) make FTU of special interest from a point of view of dust studies. Analyses were conducted by standard dust analysis methods and by dedicated analysis, as X-rays and neutron diffraction, to investigate the presence of lithium compounds due the presence of the LLL in FTU. Dust collected near the LLL presents a different elemental composition, namely Li compounds, compared to the dust collected in the rest of the vessel; in particular LiO{sub 2}, LiOH, and Li{sub 2}CO{sub 3}. On the basis of these results, the formation of Li{sub 2}CO{sub 3} is proposed via a two steps process. Results of fuel retention measured by thermal desorption spectroscopy (TDS) method show that fuel retention should not be an issue for FTU.

  17. Glass Frit Clumping And Dusting

    Energy Technology Data Exchange (ETDEWEB)

    Steimke, J. L.

    2013-09-26

    DWPF mixes a slurry of glass frit (Frit 418) and dilute (1.5 wt%) formic acid solution with high level waste in the Slurry Mix Evaporator (SME). There would be advantages to introducing the frit in a non-slurry form to minimize water addition to the SME, however, adding completely dry frit has the potential to generate dust which could clog filters or condensers. Prior testing with another type of frit, Frit 320, and using a minimal amount of water reduced dust generation, however, the formation of hard clumps was observed. To examine options and behavior, a TTQAP [McCabe and Stone, 2013] was written to initiate tests that would address these concerns. Tests were conducted with four types of glass frit; Frit 320, DWPF Frit 418, Bekeson Frit 418 and Multi-Aspirator Frit 418. The last two frits are chemically identical to DWPF Frit 418 but smaller particles were removed by the respective vendors. Test results on Frit Clumping and Dusting are provided in this report. This report addresses the following seven questions. Short answers are provided below with more detailed answers to follow. 1. Will the addition of a small amount of water, 1.5 wt%, to dry DWPF Frit 418 greatly reduce the dust generation during handling at DWPF? a. Yes, a small scale test showed that adding a little water to the frit greatly reduced dust generation during handling. 2. Will the addition of small amounts of water to the frit cause clumping that will impair frit handling at DWPF? a. No, not with Frit 418. Although clumps were observed to form when 1.5 wt% water was mixed with DWPF Frit 418, then compressed and air-dried overnight, the clumps were easily crushed and did not form the hardened material noted when Frit 320 was tested. 3. What is the measured size distribution of dust generated when dry frit is handled? (This affects the feasibility and choice of processing equipment for removing the dust generating fraction of the frit before it is added to the SME.) a. The size distribution for

  18. Glass Frit Clumping And Dusting

    Energy Technology Data Exchange (ETDEWEB)

    Steimke, J. L.

    2013-09-26

    DWPF mixes a slurry of glass frit (Frit 418) and dilute (1.5 wt%) formic acid solution with high level waste in the Slurry Mix Evaporator (SME). There would be advantages to introducing the frit in a non-slurry form to minimize water addition to the SME, however, adding completely dry frit has the potential to generate dust which could clog filters or condensers. Prior testing with another type of frit, Frit 320, and using a minimal amount of water reduced dust generation, however, the formation of hard clumps was observed. To examine options and behavior, a TTQAP [McCabe and Stone, 2013] was written to initiate tests that would address these concerns. Tests were conducted with four types of glass frit; Frit 320, DWPF Frit 418, Bekeson Frit 418 and Multi-Aspirator Frit 418. The last two frits are chemically identical to DWPF Frit 418 but smaller particles were removed by the respective vendors. Test results on Frit Clumping and Dusting are provided in this report. This report addresses the following seven questions. Short answers are provided below with more detailed answers to follow. 1. Will the addition of a small amount of water, 1.5 wt%, to dry DWPF Frit 418 greatly reduce the dust generation during handling at DWPF? a. Yes, a small scale test showed that adding a little water to the frit greatly reduced dust generation during handling. 2. Will the addition of small amounts of water to the frit cause clumping that will impair frit handling at DWPF? a. No, not with Frit 418. Although clumps were observed to form when 1.5 wt% water was mixed with DWPF Frit 418, then compressed and air-dried overnight, the clumps were easily crushed and did not form the hardened material noted when Frit 320 was tested. 3. What is the measured size distribution of dust generated when dry frit is handled? (This affects the feasibility and choice of processing equipment for removing the dust generating fraction of the frit before it is added to the SME.) a. The size distribution for

  19. Planetary Magnetosphere Probed by Charged Dust Particles

    Science.gov (United States)

    Sternovsky, Z.; Horanyi, M.; Gruen, E.; Srama, R.; Auer, S.; Kempf, S.; Krueger, H.

    2010-12-01

    In-situ and remote sensing observations combined with theoretical and numerical modeling greatly advanced our understanding planetary magnetospheres. Dust is an integral component of the Saturnian and Jovian magnetospheres where it can act as a source/sink of plasma particles (dust particles are an effective source for plasma species like O2, OH, etc. through sputtering of ice particles, for example); its distribution is shaped by electrodynamic forces coupled radiation pressure, plasma, and neutral drag, for example. The complex interaction can lead to unusual dust dynamics, including the transport, capture, and ejection of dust grains. The study of the temporal and spatial evolution of fine dust within or outside the magnetosphere thus provides a unique way to combine data from a large number of observations: plasma, plasma wave, dust, and magnetic field measurements. The dust detectors on board the Galileo and Cassini spacecrafts lead to major discoveries, including the jovian dust stream originating from Io or the in-situ sampling and analysis of the plumes of Enceladus. Recent advancement in dust detector technology enables accurate measurement of the dust trajectory and elemental composition that can greatly enhance the understanding of dust magnetorspheric interaction and indentify the source of the dust with high precision. The capabilities of a modern dust detector thus can provide support for the upcoming Europa Jupiter System Mission.

  20. Rehabilitation of Avulsed Teeth in Fractured Jaws via Bone Grafting and Implant Placement: Report of Two Cases

    Directory of Open Access Journals (Sweden)

    Anshul Jain

    2016-01-01

    Full Text Available The maxillofacial region is one of the most injury-prone areas during road traffic accidents, personal violence, falls and sports. Maxillofacial trauma can lead to breakage or avulsion of upper anterior teeth, which may cause significant aesthetic and functional problems. There are many treatment options available for rehabilitation including removable partial dentures, fixed partial dentures, crown and bridges and implant-supported prostheses.Herein, two cases are presented where implant placement was done for upper anterior teeth, which were traumatized or avulsed following maxillofacial trauma. Both patients demonstrated a history of maxillofacial trauma and had undergone open reduction and internal fixation. The first patient had a severe maxillary alveolar defect treated via autogenous bone grafting and a six-month period was given for proper integration of the bone graft. The second patient was a smoker with very poor oral hygiene and a deep bite. Thus, implant placement was not initially justified.

  1. Rehabilitation of Avulsed Teeth in Fractured Jaws via Bone Grafting and Implant Placement: Report of Two Cases

    Science.gov (United States)

    Baliga, Shridhar

    2015-01-01

    The maxillofacial region is one of the most injury-prone areas during road traffic accidents, personal violence, falls and sports. Maxillofacial trauma can lead to breakage or avulsion of upper anterior teeth, which may cause significant aesthetic and functional problems. There are many treatment options available for rehabilitation including removable partial dentures, fixed partial dentures, crown and bridges and implant-supported prostheses. Herein, two cases are presented where implant placement was done for upper anterior teeth, which were traumatized or avulsed following maxillofacial trauma. Both patients demonstrated a history of maxillofacial trauma and had undergone open reduction and internal fixation. The first patient had a severe maxillary alveolar defect treated via autogenous bone grafting and a six-month period was given for proper integration of the bone graft. The second patient was a smoker with very poor oral hygiene and a deep bite. Thus, implant placement was not initially justified. PMID:26877745

  2. Dust remobilization in fusion plasmas

    CERN Document Server

    Tolias, P; De Angeli, M; De Temmerman, G; Ripamonti, D; Riva, G; Bykov, I; Shalpegin, A; Vignitchouk, L; Brochard, F; Bystrov, K; Bardin, S; Litnovsky, A

    2016-01-01

    The first combined experimental and theoretical studies of dust remobilization by plasma forces are reported. The main theoretical aspects of remobilization are analyzed. In particular, the dominant role of adhesive forces is highlighted and generic remobilization conditions - detachment, sliding, rolling - are formulated. A novel experimental technique is proposed, based on controlled adhesion of dust grains on tungsten samples combined with detailed mapping of the dust deposition profile prior and post plasma exposure. Proof-of-principle experiments in the TEXTOR tokamak and the EXTRAP-T2R reversed-field pinch are presented. The versatile environment of the linear device Pilot-PSI allowed for experiments with different magnetic field topologies and varying plasma conditions that were complemented with camera observations.

  3. Coal dust: the real cost

    Energy Technology Data Exchange (ETDEWEB)

    Walker, S. [Independent Editorial and Technical Services, Oxford (United Kingdom)

    1998-04-01

    A recent British court case awarded retired coal miners compensation for asthma, chronic bronchitis and emphysema. Although the sums involved were small, large numbers of retired coal miners are likely to be eligible for such awards, as British safety in mines was not substantially worse than most other producers at the time, and was better than many. In some parts of the world safety standards are still poor. Dust suppression should be used on coal cutting machines, and dust controlled in transit. This may prove less expensive than it initially appears since the coal dust can be used instead of lost. This particularly important for transport in open trucks. Employers must also ensure that the safety equipment supplied is both comfortable and used. 3 refs., 5 photos.

  4. Microwave Emission from Aligned Dust

    CERN Document Server

    Lazarian, A

    2003-01-01

    Polarized microwave emission from dust is an important foreground that may contaminate polarized CMB studies unless carefully accounted for. We discuss potential difficulties associated with this foreground, namely, the existence of different grain populations with very different emission/polarization properties and variations of the polarization yield with grain temperature. In particular, we discuss observational evidence in favor of rotational emission from tiny PAH particles with dipole moments, i.e. ``spinning dust'', and also consider magneto-dipole emission from strongly magnetized grains. We argue that in terms of polarization, the magneto-dipole emission may dominate even if its contribution to total emissivity is subdominant. Addressing polarized emission at frequencies larger than approsimately 100 GHz, we discuss the complications arising from the existence of dust components with different temperatures and possibly different alignment properties.

  5. Polarized Emission from Interstellar Dust

    CERN Document Server

    Vaillancourt, J E

    2006-01-01

    Observations of far-infrared (FIR) and submillimeter (SMM) polarized emission are used to study magnetic fields and dust grains in dense regions of the interstellar medium (ISM). These observations place constraints on models of molecular clouds, star-formation, grain alignment mechanisms, and grain size, shape, and composition. The FIR/SMM polarization is strongly dependent on wavelength. We have attributed this wavelength dependence to sampling different grain populations at different temperatures. To date, most observations of polarized emission have been in the densest regions of the ISM. Extending these observations to regions of the diffuse ISM, and to microwave frequencies, will provide additional tests of grain and alignment models. An understanding of polarized microwave emission from dust is key to an accurate measurement of the polarization of the cosmic microwave background. The microwave polarization spectrum will put limits on the contributions to polarized emission from spinning dust and vibrat...

  6. Bone regeneration using the pouch-and-tunnel technique.

    Science.gov (United States)

    Azzi, Robert; Etienne, Daniel; Takei, Henry; Carranza, Fermin

    2009-10-01

    Several surgical techniques, such as the papilla preservation flap, the modified papilla preservation flap, and the sulcular incision flap, have attempted to achieve clot stabilization and graft coverage in an attempt to regenerate lost tissue due to periodontal disease. This case report focuses on soft tissue root coverage and bone regeneration in a one-wall osseous defect using the pouch-and-tunnel surgical procedure. The pouch-and-tunnel surgical technique is a minimally invasive periodontal plastic surgical procedure that uses subepithelial connective tissue as a free graft in a pouch beneath the gingival margin, created by sulcular incisions around the involved teeth. The autogenous bone graft placed in this one-wall osseous defect through a sulcular incision after root planing is protected in a stable pouch-like recipient site with an abundant blood supply. The free connective tissue graft also prevents epithelial migration into the recipient site. The use of Emdogain may help with cementogenesis around the planed root surface. This technique warrants further evaluation of cases with similar defects using this surgical procedure. (Int J Periodontics Restorative Dent 2009;29:515-521.).

  7. Smoking and Bone Health

    Science.gov (United States)

    ... supported by your browser. Home Bone Basics Lifestyle Smoking and Bone Health Publication available in: PDF (85 ... late to adopt new habits for healthy bones. Smoking and Osteoporosis Cigarette smoking was first identified as ...

  8. [Effect of lunar dust on humans: -lunar dust: regolith-].

    Science.gov (United States)

    Morimoto, Yasuo; Miki, Takeo; Higashi, Toshiaki; Horie, Seichi; Tanaka, Kazunari; Mukai, Chiaki

    2010-09-01

    We reviewed the effect of lunar dust (regolith) on humans by the combination of the hazard/exposure of regolith and microgravity of the moon. With regard to the physicochemical properties of lunar dust, the hazard-related factors are its components, fibrous materials and nanoparticles. Animal exposure studies have been performed using a simulant of lunar dust, and it was speculated that the harmful effects of the simulant lies between those of crystalline silica and titanium dioxide. Fibrous materials may not have a low solubility judging from their components. The nanoparticles in lunar dust may have harmful potentials from the view of the components. As for exposure to regolith, there is a possibility that particles larger than ones in earth (1 gravity) are respirable. In microgravity, 1) the deposition of particles of less than 1 µm in diameter in the human lung did not decrease, 2) the functions of macrophages including phagocytosis were suppressed, 3) pulmonary inflammation was changed. These data on hazard/exposure and microgravity suggest that fine and ultrafine particles in regolith may have potential hazards and risks for humans.

  9. Efficient radiative transfer in dust grain mixtures

    CERN Document Server

    Wolf, S

    2003-01-01

    The influence of a dust grain mixture consisting of spherical dust grains with different radii and/or chemical composition on the resulting temperature structure and spectral energy distribution of a circumstellar shell is investigated. The comparison with the results based on an approximation of dust grain parameters representing the mean optical properties of the corresponding dust grain mixture reveal that (1) the temperature dispersion of a real dust grain mixture decreases substantially with increasing optical depth, converging towards the temperature distribution resulting from the approximation of mean dust grain parameters, and (2) the resulting spectral energy distributions do not differ by more than 10% if >= 2^5 grain sizes are considered which justifies the mean parameter approximation and the many results obtained under its assumption so far. Nevertheless, the dust grain temperature dispersion at the inner boundary of a dust shell may amount to >>100K and has therefore to be considered in the cor...

  10. Dust Mitigation for the Lunar Surface Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The lunar surface is to a large extent covered with a dust layer several meters thick. Known as lunar regolith, it poses a hazard in the form of dust clouds being...

  11. Dust transport into Martian polar latitudes

    Science.gov (United States)

    Murphy, J. R.; Pollack, J. B.

    1992-01-01

    The presence of suspended dust in the Martian atmosphere, and its return to the planet's surface, is implicated in the formation of the polar layered terrain and the dichotomy in perennial CO2 polar cap retention in the two hemispheres. A three dimensional model was used to study Martian global dust storms. The model accounts for the interactive feedbacks between the atmospheric thermal and dynamical states and an evolving radiatively active suspended dust load. Results from dust storm experiments, as well as from simulations in which there is interest in identifying the conditions under which surface dust lifting occurs at various locations and times, indicate that dust transport due to atmospheric eddy motions is likely to be important in the arrival of suspended dust at polar latitudes. The layered terrain in both polar regions of Mars is interpreted as the reality of cyclical episodes of volatile (CO2, H2O) and dust deposition.

  12. Durable Dust Repellent Coating for Metals Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Durable Dust Repellent Coating (DDRC) consists of nano-phase silica, titania, or other oxide coatings to repel dust in a vacuum environment over a wide range of...

  13. Early dust evolution in protostellar accretion disks

    OpenAIRE

    2000-01-01

    We investigate dust dynamics and evolution during the formation of a protostellar accretion disk around intermediate mass stars via 2D numerical simulations. Using three different detailed dust models, compact spherical particles, fractal BPCA grains, and BCCA grains, we find that even during the early collapse and the first 10,000 yr of dynamical disk evolution, the initial dust size distribution is strongly modified. Close to the disk's midplane coagulation produces dust particles of sizes ...

  14. History and Applications of Dust Devil Studies

    Science.gov (United States)

    Lorenz, Ralph D.; Balme, Matthew R.; Gu, Zhaolin; Kahanpää, Henrik; Klose, Martina; Kurgansky, Michael V.; Patel, Manish R.; Reiss, Dennis; Rossi, Angelo Pio; Spiga, Aymeric; Takemi, Tetsuya; Wei, Wei

    2016-11-01

    Studies of dust devils, and their impact on society, are reviewed. Dust devils have been noted since antiquity, and have been documented in many countries, as well as on the planet Mars. As time-variable vortex entities, they have become a cultural motif. Three major stimuli of dust devil research are identified, nuclear testing, terrestrial climate studies, and perhaps most significantly, Mars research. Dust devils present an occasional safety hazard to light structures and have caused several deaths.

  15. Dust levitation about Itokawa's equator

    Science.gov (United States)

    Hartzell, C.; Zimmerman, M.; Takahashi, Y.

    2014-07-01

    Introduction: Electrostatic dust motion has been hypothesized to occur on the asteroids, due to the observations of the Eros dust ponds [1] and the potential presence of such a phenomenon on the Moon [2]. There are two phases of electrostatic dust motion: lofting and the subsequent trajectories. The feasibility of electrostatic dust lofting can be assessed by comparing the strength of the electrostatic force to the gravity and cohesion which hold the grain on to the surface [3--5]. The motion of the dust grains after they detach from the surface can be described as either ballistic, escaping, or levitating. We are interested in dust levitation because it could potentially redistribute grains on the surface of an asteroid (for instance, producing the Eros dust ponds) and it could also be hazardous to spacecraft. Specifically, levitating dust could obscure the observations of surface-based spacecraft or possibly trigger obstacle avoidance routines during landing. Dust Levitation: Dust levitation is defined as the altitude oscillation of grains prior to their redeposition on the surface of an asteroid. Levitation occurs about equilibria where the electrostatic and gravity forces on the grain are equal and opposite. An equilibrium state is defined as a position and charge for a specific grain size. We have previously identified equilibria using a 1D plasma model and a simple gravity model for Itokawa [6]. In this simple model, the largest grain that was capable of stable levitation above Itokawa was 3 microns (in radius) [6]. Additionally, we have shown that levitating dust grains follow the variation in the equilibria for a rotating asteroid (i.e., the grain continues to oscillate about an equilibrium state that approaches the surface) [7]. Due to the nonspherical shape of Itokawa, both the gravity and plasma environments are much more complicated than the 1D approximations made in our previous work. Thus, in order to accurately assess the feasibility of dust

  16. Linear and nonlinear excitations in complex plasmas with nonadiabatic dust charge fluctuation and dust size distribution

    Institute of Scientific and Technical Information of China (English)

    Zhang Li-Ping; Xue Ju-Kui; Li Yan-Long

    2011-01-01

    Both linear and nonlinear excitation in dusty plasmas have been investigated including the nonadiabatic dust charge fluctuation and Gaussian size distribution dust particles.A linear dispersion relation and a Korteweg-de VriesBurgers equation governing the dust acoustic shock waves are obtained.The relevance of the instability of wave and the wave evolution to the dust size distribution and nonadiabatic dust charge fluctuation is illustrated both analytically and numerically.The numerical results show that the Gaussian size distribution of dust particles and the nonadiabatic dust charge fluctuation have strong common influence on the propagation of both linear and nonlinear excitations.

  17. Origin of Harmattan dust settled in Northern Ghana – Long transported or local dust?

    DEFF Research Database (Denmark)

    Lyngsie, Gry; Awadzi, Theodore W; Breuning-Madsen, Henrik

    2011-01-01

    compositions of the bulk dust samples. Traces of minerals in the clay fraction of the Harmattan period dust may have their origin in the Bodélé Depression or other saline environments. The Harmattan dust deposited in Ghana shows only little resemblance to dust from the Chad basin and with Harmattan dust...... deposited in Niger. This study therefore suggests that the dust deposited during the Harmattan period in northern Ghana is not under significant influence of sediments from the Bodélé Depression. Similarity in the mineral and elemental composition of the dust from both the Harmattan and Monsoon periods...

  18. Modeling of dust deposition in central Asia

    Science.gov (United States)

    The deposition of dust particles has a significant influence on the global bio-geochemical cycle. Currently, the lack of spatiotemporal data creates great uncertainty in estimating the global dust budget. To improve our understanding of the fate, transport and cycling of airborne dust, there is a ne...

  19. House dust extracts contain potent immunological adjuvants

    NARCIS (Netherlands)

    Beukelman, C.J.; Dijk, H. van; Aerts, P.C.; Rademaker, P.M.; Berrens, L.; Willers, J.M.N.

    1987-01-01

    A crude aqueous extract of house dust and two house dust subfractions were tested for adjuvant activity in a sensitivity assay performed in mice. Evidence is presented that house dust contains at least two potent immunological adjuvants. One of these, present in both subfractions, was probably endot

  20. Thirteen years of Aeolian dust dynamics in a desert region (Negev desert, Israel): analysis of horizontal and vertical dust flux, vertical dust distribution and dust grain size

    NARCIS (Netherlands)

    Offer, Z.Y.; Goossens, D.

    2004-01-01

    At Sede Boqer (northern Negev desert, Israel), aeolian dust dynamics have been measured during the period 1988–2000. This study focuses on temporal records of the vertical and horizontal dust flux, the vertical distribution of the dust particles in the atmosphere, and the grain size of the particles

  1. Immune and cellular impacts in the autogenous Aedes caspius larvae after experimentally-induced stress: Effects of Bacillus thuringiensis infection

    Directory of Open Access Journals (Sweden)

    Ashraf M. Ahmed

    2013-01-01

    Full Text Available Insects possess effective defense mechanisms against pathogens via induction of antimicrobial immune and oxidative stress responses. In this study, immune impact and histological damages in the gastric caeca have been investigated in the 3rd instar larvae of the autogenous Aedes caspius upon infection with Bacillus thuringiensis (Bt. Data showed a significant increase in phenoloxidase (PO activity by 1.23 folds at 4 h post-infection which then reduced to the normal level at 8 h post-infection and until larval death. Besides, the nitric oxide (NO titer was significantly increased by 1.4 folds at 4 h post-infection, then, reduced down to its normal level at 8 h post-infection, after which, it was significantly decreasing by time until being hardly detected at 44 h post-infection compared to that of control mosquitoes. Moreover, percentages of cellular apoptosis were significantly elevating from 6 to 48 h post-infection. Consequently, cytological damages in the epithelium and the microvilli of the gastric caeca were observed at 48 h post-infection. Finally, larval body sizes were significantly smaller prior to death (at 48 h post-infection. Taken together, these data suggest further modes of action of Bt as inhibiting the antibacterial immune responses, inducing cellular apoptosis prior to damaging the epithelium of gastric caeca. This may explain – partially at least – the irresistibility and high pathogenicity of Bt against mosquito vector, which may help in understanding, and hence, overcoming the developing resistance by some mosquito vectors to some mosquitocidal bacteria. This may help in improving the biocontrol measures against mosquito vectors.

  2. Autogenic training and cognitive self-hypnosis for the treatment of recurrent headaches in three different subject groups.

    Science.gov (United States)

    ter Kuile, M M; Spinhoven, P; Linssen, A C; Zitman, F G; Van Dyck, R; Rooijmans, H G

    1994-09-01

    The aims of this study were to (a) investigate the efficacy of autogenic training (AT) and cognitive self-hypnosis training (CSH) for the treatment of chronic headaches in comparison with a waiting-list control (WLC) condition, (b) investigate the influence of subject recruitment on treatment outcome and (c) explore whether the level of hypnotizability is related to therapy outcome. Three different subjects groups (group 1, patients (n = 58) who were referred by a neurological outpatient clinic; group 2, members (n = 48) of the community who responded to an advertisement in a newspaper; and group 3, students (n = 40) who responded to an advertisement in a university newspaper) were allocated at random to a therapy or WLC condition. During treatment, there was a significant reduction in the Headache Index scores of the subjects in contrast with the controls. At post-treatment and follow-up almost no significant differences were observed between the 2 treatment conditions or the 3 referral sources regarding the Headache Index, psychological distress (SCL-90) scores and medication use. Follow-up measurements indicated that therapeutic improvement was maintained. In both treatment conditions, the high-hypnotizable subjects achieved a greater reduction in headache pain at post-treatment and follow-up than did the low-hypnotizable subjects. It is concluded that a relatively simple and highly structured relaxation technique for the treatment of chronic headache subjects may be preferable to more complex cognitive hypnotherapeutic procedures, irrespective of the source of recruitment. The level of hypnotic susceptibility seems to be a subject characteristic which is associated with a more favourable outcome in subjects treated with AT or CSH.

  3. Comparative effects of different transplantation ways of bone marrow-derived mesenchymal stem cells on damage repair of lung injury in rats exposed to silica dust%骨髓间充质干细胞移植方式对染矽尘大鼠肺损伤修复作用比较

    Institute of Scientific and Technical Information of China (English)

    黄明; 周永梅; 程樱; 王艳艳; 陈铿铿; 燕玲; 赖关朝; 梁伟辉

    2015-01-01

    数、血红蛋白水平、红细胞压积均分别高于对照组(P<0.05)。气管组大鼠血清尿素氮水平高于静脉组(P<0.05),染尘组大鼠血清铜蓝蛋白水平高于其余3组(P<0.05)。4组大鼠周围血血小板和血清丙氨酸氨基转移酶、天冬氨酸氨基转移酶、肌酸激酶、总蛋白、白蛋白、球蛋白、肌酐等指标的差异均无统计学意义(P>0.05)。结论经静脉和经气管2种BMMSCs移植方式对矽尘所致大鼠肺损伤均具有修复作用,2种移植方式的修复作用没有显著性差异。%Objective To compare different effects of intravenous injection and trachea transplantation ways of bone marrow-derived mesenchymal stem cell ( BMMSC) on the damage repair of lung injury in rats exposed to silica dust. Methods BMMSCs were isolated from 14 specific pathogen free healthy male SD rats, cultured and amplified in vitro, while 48 rats of the same kind were randomly divided into control group, silica-exposed group, intravenous injection way group, and trachea way group, 12 rats in each group.The latter 3 groups were injected intratracheally with 1.0 mL of 40 g/L sterile silica dust suspension while control group was given 1.0 mL of sterile physiological sodium chloride solution. Then, intravenous injection way group and trachea way group were injected with 0.5 mL of BMMSCs ( cell density, 5 ×109/L) through the tail intravenous injection and trachea respectively.Rats were weighted and executed on day 28, and lung organ coefficients were calculated.The pathomorphological changes in lung tissues were observed and alveolar inflammation and pulmonary fibrosis were scored, while hydroxyproline ( HYP ) , transforming growth factor-beta 1 ( TGF-β1 ) and tumor necrosis factor-α( TNF-α) concentration of lung, routine blood test and some biochemical indices of peripheral blood were also detected.Results The lung organ coefficients of silica-exposed group, intravenous injection

  4. Dust tori in radio galaxies

    NARCIS (Netherlands)

    van der Wolk, G.; Barthel, P. D.; Peletier, R. F.; Pel, J. W.

    2010-01-01

    Aims: We investigate the quasar - radio galaxy unification scenario and detect dust tori within radio galaxies of various types. Methods: Using VISIR on the VLT, we acquired sub-arcsecond (~0.40 arcsec) resolution N-band images, at a wavelength of 11.85 μm, of the nuclei of a sample of 27 radio gala

  5. Dust in the interplanetary medium

    Energy Technology Data Exchange (ETDEWEB)

    Mann, Ingrid; Lamy, Herve [Belgian Institute for Space Aeronomy, Brussels (Belgium); Czechowski, Andrzej [Space Research Center, Polish Academy of Sciences, Warsaw (Poland); Meyer-Vernet, Nicole; Zaslavsky, Arnaud, E-mail: ingrid.mann@aeronomie.b [LESIA, Observatoire de Paris, Meudon (France)

    2010-12-15

    The mass density of dust particles that form from asteroids and comets in the interplanetary medium of the solar system is, near 1 AU, comparable to the mass density of the solar wind. It is mainly contained in particles of micrometer size and larger. Dust and larger objects are destroyed by collisions and sublimation and hence feed heavy ions into the solar wind and the solar corona. Small dust particles are present in large number and as a result of their large charge to mass ratio deflected by electromagnetic forces in the solar wind. For nanodust particles of sizes {approx_equal}1-10 nm, recent calculations show trapping near the Sun and outside from about 0.15 AU ejection with velocities close to solar wind velocity. The fluxes of ejected nanodust are detected near 1 AU with the plasma wave instrument onboard the STEREO spacecraft. Although such electric signals have been observed during dust impacts before, the interpretation depends on several different parameters and data analysis is still in progress.

  6. Bone development

    DEFF Research Database (Denmark)

    Tatara, M.R.; Tygesen, Malin Plumhoff; Sawa-Wojtanowicz, B.

    2007-01-01

    The objective of this study was to determine the long-term effect of alpha-ketoglutarate (AKG) administration during early neonatal life on skeletal development and function, with emphasis on bone exposed to regular stress and used to serve for systemic changes monitoring, the rib. Shropshire ram...... lambs were randomly assigned to two weight-matched groups at birth. During the first 14 days of life AKG was administered orally to the experimental group (n=12) at the dosage of 0.1 g/kg body weight per day, while the control group (n=11) received an equal dose of the vehicle. Lambs were slaughtered...... has a long-term effect on skeletal development when given early in neonatal life, and that changes in rib properties serve to improve chest mechanics and functioning in young animals. Moreover, neonatal administration of AKG may be considered as an effective factor enhancing proper development...

  7. Fibular Allograft and Demineralized Bone Matrix for the Treatment of Slipped Capital Femoral Epiphysis.

    Science.gov (United States)

    Murray, Travis; Morscher, Melanie A; Krahe, Amy M; Adamczyk, Mark J; Weiner, Dennis S

    2016-05-01

    Previous studies documented the use of fibular allograft in the treatment of slipped capital femoral epiphysis (SCFE) with bone graft epiphysiodesis (BGE). This study describes the results of using a 10-mm diameter premilled fibular allograft packed with demineralized bone matrix placed across the physis in an open surgical approach under image intensification. A review identified 45 cases of BGE using fibular allograft and demineralized bone matrix in 34 patients with a diagnosis of SCFE performed by a single surgeon during an 8-year period. Thirty-four cases (25 patients) had at least 1 year of follow-up and were included in the study. Medical records were reviewed for complications, subsequent surgeries, and time to physeal closure. Of the 34 cases included, there were no cases of acute chondrolysis. Complications included 1 case of bone graft extrusion that required surgical replacement and 1 re-slip requiring surgical stabilization. Five cases of avascular necrosis (AVN) were encountered (1 unstable slip with total head AVN, and 4 stable slips with 3 total head and 1 partial head AVN). In 1 patient, small loose bony fragments were noted on postoperative radiographs that appeared outside of the articular surface of the hip and were asymptomatic. Two patients encountered wound healing issues that resolved with appropriate wound care. In light of the occurrence of AVN in stable cases, BGE with autogenous corticocancellous graft is preferable to BGE with autologous fibular graft for the treatment of SCFE. [Orthopedics. 2016; 39(3):e519-e525.].

  8. Influence of Fly Ash and Slag Powder on Autogenous Shrinkage of Cement Mortars%粉煤灰和矿粉对水泥胶砂自收缩的影响

    Institute of Scientific and Technical Information of China (English)

    肖佳; 陈雷; 邢昊

    2011-01-01

    试验研究了粉煤灰和矿粉对水泥胶砂自收缩的影响.结果表明:当胶砂比(质量比)为1∶0.5,水胶比(质量比)为0.3时,随水化龄期延长,水泥胶砂自收缩增大,早期自收缩发展急剧.粉煤灰降低了水泥胶砂的自收缩,随着粉煤灰掺量(质量分数)增大,水泥胶砂自收缩减小;掺10%和20%粉煤灰水泥胶砂的21d自收缩较纯水泥胶砂分别下降了21.1%和29.5%.水化早期(5d前),矿粉掺量(质量分数)在10%~20%时,随着矿粉掺量增大,水泥胶砂自收缩降低;掺10%和20%矿粉水泥胶砂的21 d自收缩较纯水泥胶砂分别增加了11.1%和6.6%.%The influence of fly ash and slag powder on the autogenous shrinkage of cement mortars was studied. The experiment test results indicate that the autogenous shrinkage of cement mortar made with 1:0. 5 binder to sand ratio(by mass) and 0. 3 water to binder ratio(by mass) increases with development of hydration. At early age, rate of autogenous shrinkage develops sharply. Addition of fly ash reduces the autogenous shrinkage of cement mortar, and the autogenous shrinkage of cement mortar decreases with increase of fly ash content(by mass). Compared to pure cement mortar, after hydrated for 21 d , the 10% and 20% of fly ash addition reduce autogenous shrinkage of cement mortar by 21. 1% and 29. 5% respectively. Originally within 5 d, the 10%- 20% (by mass) of slag powder addition decreases autogenous shrinkage of cement mortar. Compared to pure cement mortar, after hydrated for 21 d, the 10% and 20% of slag powder addition increase autogenous shrinkage of cement mortar by 11. 1% and 6. 6% respectively.

  9. Comparative evaluation of platelet-rich fibrin and autogenous bone graft for the treatment of infrabony defects in chronic periodontitis: Clinical, radiological, and surgical reentry

    Directory of Open Access Journals (Sweden)

    Sneha Galav

    2016-01-01

    Conclusion: Both ABG and PRF can be used predictably to reconstruct lost periodontal structures as indicated by PPD reduction and RAL gain. However, in terms of osseous defect fill, ABG yields more definitive outcome than PRF.

  10. Modeling Thermal Dust Emission and Implications

    Science.gov (United States)

    Liang, Zhuohan

    2014-01-01

    An accurate model of thermal dust emission at the far-infrared and millimeter wavelengths is important for studying the cosmic microwave background anisotropies and for understanding the cycling of matter and energy between stars and the interstellar medium. I will present results of fitting all-sky one-component dust models with fixed or variable emissivity spectral index to the 210-channel dust spectra from the COBE-FIRAS, the 100 - 240 μm maps from the COBE-DIRBE, and the 94 GHz dust map from the WMAP. I will also discuss the implications of the analysis on understanding astrophysical processes and the physical properties of dust grains.

  11. Reducing Coal Dust With Water Jets

    Science.gov (United States)

    Gangal, M. D.; Lewis, E. V.

    1985-01-01

    Jets also cool and clean cutting equipment. Modular pick-and-bucket miner suffers from disadvantage: Creates large quantities of potentially explosive coal dust. Dust clogs drive chain and other parts and must be removed by hand. Picks and bucket lips become overheated by friction and be resharpened or replaced frequently. Addition of oscillating and rotating water jets to pick-and-bucket machine keeps down dust, cools cutting edges, and flushes machine. Rotating jets wash dust away from drive chain. Oscillating jets cool cutting surfaces. Both types of jet wet airborne coal dust; it precipitates.

  12. Linear Alkylbenzenesulfonates in indoor Floor Dust

    DEFF Research Database (Denmark)

    Wolkoff, Peder; Madsen, Jørgen Øgaard

    1999-01-01

    The amount of Linear Alkylbenzenesulfonates (LAS) in the particle fraction of floor dust sampled from 7 selected public buildings varied between 34 and 1500 microgram per gram dust, while the contents of the fibre fractions generally were higher with up to 3500 microgram LAS/g dust. The use...... of a cleaning agent with LAS resulted in an increase of the amount of LAS in the floor dust after floor wash relative to just before floor wash. However, the most important source of LAS in the indoor floor dust appears to be residues of detergent in clothing. Thus, a newly washed shirt contained 2960 microgram...

  13. Global amount of dust in the universe

    CERN Document Server

    Fukugita, Masataka

    2011-01-01

    It is pointed out that the total amount of dust in the Universe that is produced in stellar evolution in the entire cosmic time is consistent with the observed amount, if we add to the dust amount inferred for galactic discs the amount recently uncovered in galactic haloes and the surrounding of galaxies in reddening of the quasar light passing through the vicinity of galaxies. The inventory concerning the dust closes. This implies that dust produced from stars should survive effectively for the cosmic time, and that a substantial amount of dust is produced in the burning phase of evolved stars of intermedaite mass.

  14. Numerical Prediction of Dust. Chapter 10

    Science.gov (United States)

    Benedetti, Angela; Baldasano, J. M.; Basart, S.; Benincasa, F.; Boucher, O.; Brooks, M.; Chen, J. P.; Colarco, P. R.; Gong, S.; Huneeus, N.; Jones, L; Lu, S.; Menut, L.; Mulcahy, J.; Nickovic, S.; Morcrette, J.-J.; Perez, C.; Reid, J. S.; Sekiyama, T. T.; Tanaka, T.; Terradellas, E.; Westphal, D. L.; Zhang, X.-Y.; Zhou, C.-H.

    2013-01-01

    Covers the whole breadth of mineral dust research, from a scientific perspective Presents interdisciplinary work including results from field campaigns, satellite observations, laboratory studies, computer modelling and theoretical studies Explores the role of dust as a player and recorder of environmental change This volume presents state-of-the-art research about mineral dust, including results from field campaigns, satellite observations, laboratory studies, computer modelling and theoretical studies. Dust research is a new, dynamic and fast-growing area of science and due to its multiple roles in the Earth system, dust has become a fascinating topic for many scientific disciplines. Aspects of dust research covered in this book reach from timescales of minutes (as with dust devils, cloud processes, and radiation) to millennia (as with loess formation and oceanic sediments), making dust both a player and recorder of environmental change. The book is structured in four main parts that explore characteristics of dust, the global dust cycle, impacts of dust on the Earth system, and dust as a climate indicator. The chapters in these parts provide a comprehensive, detailed overview of this highly interdisciplinary subject. The contributions presented here cover dust from source to sink and describe all the processes dust particles undergo while travelling through the atmosphere. Chapters explore how dust is lifted and transported, how it affects radiation, clouds, regional circulations, precipitation and chemical processes in the atmosphere, and how it deteriorates air quality. The book explores how dust is removed from the atmosphere by gravitational settling, turbulence or precipitation, how iron contained in dust fertilizes terrestrial and marine ecosystems, and about the role that dust plays in human health. We learn how dust is observed, simulated using computer models and forecast. The book also details the role of dust deposits for climate reconstructions

  15. 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

  16. Orchestration of bone remodeling

    NARCIS (Netherlands)

    Moester, Martiene Johanna Catharina

    2014-01-01

    In healthy individuals, a balance exists between bone formation and resorption. Disruption of this balance can lead to higher or lower bone mass, and disease such as osteoporosis. Treatment for osteoporosis generally inhibits bone resorption, but does not rebuild bone to a healthy strength. More kno

  17. 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.

  18. Bone Marrow Diseases

    Science.gov (United States)

    Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains stem cells. The stem cells can ... the platelets that help with blood clotting. With bone marrow disease, there are problems with the stem ...

  19. Ice nucleation properties of agricultural soil dusts

    Science.gov (United States)

    Steinke, Isabelle; Funk, Roger; Busse, Jacqueline; Iturri, Antonela; Kirchen, Silke; Leue, Martin; Möhler, Ottmar; Schwartz, Thomas; Sierau, Berko; Toprak, Emre; Ulrich, Andreas; Hoose, Corinna; Leisner, Thomas

    2015-04-01

    Soil dust particles emitted from agricultural areas contain large amounts of organic material such as fungi, bacteria and plant debris. Being carrier for potentially highly ice-active biological particles, agricultural soil dusts are candidates for being very ice-active as well. In this work, we present ice nucleation experiments conducted in the AIDA cloud chamber. We investigated the ice nucleation efficiency of four types of soil dust from different regions of the world. Results are presented for the immersion freezing and the deposition nucleation mode: all soil dusts show higher ice nucleation efficiencies than desert dusts, especially at temperatures above 254 K. For one soil dust sample, the effect of heat treatments was investigated. Heat treatments did not affect the ice nucleation efficiency which presumably excludes primary biological particles as the only source of the increased ice nucleation efficiency. Therefore, organo-mineral complexes or organic compounds may contribute substantially to the high ice nucleation activity of agricultural soil dusts.

  20. Dust Measurements in the Outer Solar System

    CERN Document Server

    Grün, E; Landgraf, M; Grün, Eberhard; Krüger, Harald; Landgraf, Markus

    1999-01-01

    Dust measurements in the outer solar system are reviewed. Only the plasma wave instrument on board Voyagers 1 and 2 recorded impacts in the Edgeworth-Kuiper belt (EKB). Pioneers 10 and 11 measured a constant dust flux of 10-micron-sized particles out to 20 AU. Dust detectors on board Ulysses and Galileo uniquely identified micron-sized interstellar grains passing through the planetary system. Impacts of interstellar dust grains onto big EKB objects generate at least about a ton per second of micron-sized secondaries that are dispersed by Poynting-Robertson effect and Lorentz force. We conclude that impacts of interstellar particles are also responsible for the loss of dust grains at the inner edge of the EKB. While new dust measurements in the EKB are in an early planning stage, several missions (Cassini and STARDUST) are en route to analyze interstellar dust in much more detail.

  1. A lunar dust simulant: CLDS-i

    Science.gov (United States)

    Tang, Hong; Li, Xiongyao; Zhang, Sensen; Wang, Shijie; Liu, Jianzhong; Li, Shijie; Li, Yang; Wu, Yanxue

    2017-02-01

    Lunar dust can make serious damage to the spacecrafts, space suits, and health of astronauts, which is one of the most important problems faced in lunar exploration. In the case of rare lunar dust sample, CLDS-i with high similarity to the real lunar dust is an important objective for studying dust protection and dust toxicity. The CLDS-i developed by the Institute of Geochemistry Chinese Academy Sciences contains ∼75 vol% glass and a little nanophase metal iron (np-Fe0), and with a median particle size about 500 nm. The CLDS-i particles also have complicated shape and sharp edges. These properties are similar to those of lunar dust, and make the CLDS-i can be applied to many fields such as the scientific researches, the treatment technology and toxicological study of lunar dust.

  2. Orthodontically guided bone transport in the treatment of alveolar cleft: A case report

    Science.gov (United States)

    Gómez, Elena; Otero, Marta; Berraquero, Rosario; Wucherpfennig, Begona; Hernández-Godoy, Juan; Guiñales, Jorge; Vincent, Germán; Burgueño, Miguel

    2016-01-01

    Introduction Conventional treatments are sometimes not possible in certain alveolar cleft cases due to the severity of the gap which separates the fragments. Various management strategies have been proposed, including sequential surgical interventions or delaying treatment until adulthood to then carry out maxillary osteotomies. A further alternative approach has also been proposed, involving the application of bone transport techniques to mobilise the osseous fragments and thereby reduce the gap between lateral fragments and the premaxilla. Case Report We introduce the case of a 10-year-old patient who presented with a bilateral alveolar cleft and a severe gap. Stable occlusion between the premaxilla and the mandible was achieved following orthodontic treatment, making it inadvisable to perform a retrusive osteotomy of the premaxilla in order to close the alveolar clefts. Faced with this situation, it was decided we would employ a bone transport technique under orthodontic guidance using a dental splint. This would enable an osseous disc to be displaced towards the medial area and reduce the interfragmentary distance. During a second surgical intervention, closure of the soft tissues was performed and the gap was filled in using autogenous bone. Conclusions The use of bone transport techniques in selected cases allows closure of the osseous defect, whilst also preserving soft tissues and reducing the amount of bone autograft required. In our case, we were able to respect the position of the premaxilla and, at the same time, generate new tissues at both an alveolar bone and soft tissue level with results which have remained stable over the course of time. Key words:Alveolar cleft, bone transport, graft. PMID:26855699

  3. 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.

  4. Effect of nano-hydroxyapatite/collagen composite and bone morphogenetic protein-2 on lumbar intertransverse fusion in rabbits

    Institute of Scientific and Technical Information of China (English)

    孙天胜; 关凯; 时述山; 朱兵; 郑永军; 崔福斋; 张伟; 廖素三

    2004-01-01

    Objective: To investigate the effect of nano-hydroxyapatite/collagen (nHA/collagen) composite as a graft extender and enhancer when combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) on lumbar intertransverse fusion in rabbits.Methods: Sixty-four adult female New Zealand white rabbits, aged 1 year and weighing 3.5-4.5 kg, underwent similar posterolateral intertransverse process arthrodesis and were randomly divided into 4 groups based on different grafts: autogenous cancellous bone alone (ACB group), nHA/collagen alone (HAC group), half autogenous cancellous bone and half nHA/collagen (ACB+HAC group) and nHA/collagen combined with rhBMP-2 (HAC+BMP group). The fusion masses were analyzed by manual palpation, radiography, biomechanical testing and histological examination. Results: Fusion was observed in 4 cases in the 6th week and in 5 cases in the 10th week after surgery in ACB group. No case showed fusion in HAC group. In ACB+HAC group, there was fusion in 3 cases in the 6th week and in 4 cases in the 10th week after surgery. In HAC+BMP group, fusion in 1 case was found in the 4th week, in 5 cases in the 6th week and in 6 cases in the 10th week after surgery. It suggested that ACB, ACB+HAC and HAC+BMP groups showed similar fusion ratio and mechanical strength in the 6th and 10th week after surgery. According to the microstructure analysis of the samples, nHA/collagen had no negative effect when implanted together with ilium autograft. In HAC+BMP group, new bone-like tissue was observed in the 2nd week postoperatively, and nearly all of the implanted composites were replaced by mature bone matrix and new bones in 10th week postoperatively.Conclusions: The nHA/collagen, especially combined with rhBMP-2, is a promising bone substitute, for it has quick biodegradation, fine bone-bending ability, and high osteoconductivity on posterolateral spinal fusion in rabbits.

  5. 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

  6. Regional characteristics of dust events in China

    Institute of Scientific and Technical Information of China (English)

    WANGShigong; WANGJinyan; ZHOUZijiang; SHANGKezheng; YANGDebao; ZHAO

    2003-01-01

    The regional characteristics of dust events in China has been mainly studied by using the data of dust storm,wind-blown sand and floating dust from 338 observation stations through China from 1954 to 2000.The results of this study are as follows:(1)In China,there are two high frequent areas of dust events,one is located in the area of Minfeng and Hotan in the South xinjiang Basin,the other is situated in the area of Minqin and Jilantai in the Hexi Region.Furthermore,the spatial distributions of the various types of dust events are different.The dust storms mainly occur in the arid and semiarid areas covering the deserts and the areas undergoing desertification in northern China.Wind-blown sand and floating-dust not only occur in the areas where dust storms occur,but also extend to the neighboring areas.The range of wind-blown sand extends northeastward and southeastward,but floating-dust mainly extends southeastward to the low-latitude region such as the East China Plain and the area of the middloe and lower reaches of the Yangtze River.Compared with wind-blown sand,the floating-dust seldom occurs in the high latitude areas such as North xinjiang and Northeast China.(2)The affected areas of dust storms can be divided into seven sub-regions,that is,North Xinjiang Region,South Xinjiang Region,Hexi Region,Qaidam Basin Region,Hetao Region.Northeastem China Region and Qinghai-Xizang (Tibet) Region.The area of the most frequent occurrence of dust storms and floating-dust is in South Xinjiang Region,and of wind-blown sang in the Hexi Region.In general,the frequency of dust events in all the seven regions shows a decreasing thendency from 1954 to 2000,but there are certain differences between various dust events in different regions.The maximum interannual change and ariance of dust events during this time happened in South Xinjiang Region and Hexi Region.The udst events generally occur most frequently in April in most parts of China.The spring occurred days of dust events

  7. Within patient radiological comparative analysis of the performance of two bone graft extenders utilized in posterolateral lumbar fusion: a retrospective case series

    Directory of Open Access Journals (Sweden)

    Geoffrey eStewart

    2016-01-01

    Full Text Available Two bone graft extenders differing in chemical composition were implanted contralaterally in 27 consecutive patients undergoing instrumented posterolateral lumbar fusion as standard of care. Bone marrow aspirate and autogenous bone graft were equally combined either with β-tricalcium phosphate (β-TCP or a hybrid biomaterial (containing hyaluronic acid but lacking a calcium salt and implanted between the transverse processes. Fusion status on each side of the vertebrae was retrospectively graded (1-5 scale on AP planar X-ray at multiple visits as available, through approximately month 12. Additionally, consolidation or resorption since prior visit for each treatment was recorded. Sides receiving β-TCP extender showed marked resorption prior to bone consolidation during the first 6 months. By contrast, sides receiving the hybrid biomaterial containing integrated hyaluronic acid showed rapid bone consolidation by week 6-8, with maintenance of initial bone volume through month 12. Fusion grade was superior for the hybrid biomaterial, differing significantly from β-TCP at day 109 and beyond. Fusion success at >month 12 was 92.9% vs 67.9% for the hybrid biomaterial and β-TCP-treated sides, respectively. The hybrid biomaterial extender demonstrated a shortened time to fusion compared to the calcium-based graft. Mode of action has been demonstrated in the literature to differ between these compositions. Therefore, choice of synthetic biomaterial composition may significantly influence mode of action of cellular events regulating appositional bone growth.

  8. Coupling Mars' Dust and Water Cycles: Effects on Dust Lifting Vigor, Spatial Extent and Seasonality

    Science.gov (United States)

    Kahre, M. A.; Hollingsworth, J. L.; Haberle, R. M.; Montmessin, F.

    2012-01-01

    The dust cycle is an important component of Mars' current climate system. Airborne dust affects the radiative balance of the atmosphere, thus greatly influencing the thermal and dynamical state of the atmosphere. Dust raising events on Mars occur at spatial scales ranging from meters to planet-wide. Although the occurrence and season of large regional and global dust storms are highly variable from one year to the next, there are many features of the dust cycle that occur year after year. Generally, a low-level dust haze is maintained during northern spring and summer, while elevated levels of atmospheric dust occur during northern autumn and winter. During years without global-scale dust storms, two peaks in total dust loading were observed by MGS/TES: one peak occurred before northern winter solstice at Ls 200-240, and one peak occurred after northern winter solstice at L(sub s) 305-340. These maxima in dust loading are thought to be associated with transient eddy activity in the northern hemisphere, which has been observed to maximize pre- and post-solstice. Interactive dust cycle studies with Mars General Circulation Models (MGCMs) have included the lifting, transport, and sedimentation of radiatively active dust. Although the predicted global dust loadings from these simulations capture some aspects of the observed dust cycle, there are marked differences between the simulated and observed dust cycles. Most notably, the maximum dust loading is robustly predicted by models to occur near northern winter solstice and is due to dust lifting associated with down slope flows on the flanks of the Hellas basin. Thus far, models have had difficulty simulating the observed pre- and post- solstice peaks in dust loading. Interactive dust cycle studies typically have not included the formation of water ice clouds or their radiative effects. Water ice clouds can influence the dust cycle by scavenging dust from atmosphere and by interacting with solar and infrared radiation

  9. Multiscale Modeling of Bone

    Science.gov (United States)

    2014-12-01

    DISEASE Both age and disease can affect the structure of bone, the effects of which are often similar. The most common bone disease is osteoporosis ... Osteoporosis is a disease that results in reduced bone mass and density. This reduction of bone mass and density has a greater impact on trabecular...Bone loss in females is linked to a decrease in estrogen ; the decrease of estrogen associated with menopause increases osteoclast activity [89]. This

  10. Reducing aluminum dust explosion hazards: case study of dust inerting in an aluminum buffing operation.

    Science.gov (United States)

    Myers, Timothy J

    2008-11-15

    Metal powders or dusts can represent significant dust explosion hazards in industry, due to their relatively low ignition energy and high explosivity. The hazard is well known in industries that produce or use aluminum powders, but is sometimes not recognized by facilities that produce aluminum dust as a byproduct of bulk aluminum processing. As demonstrated by the 2003 dust explosion at aluminum wheel manufacturer Hayes Lemmerz, facilities that process bulk metals are at risk due to dust generated during machining and finishing operations [U.S. Chemical Safety and Hazard Investigation Board, Investigation Report, Aluminum Dust Explosion Hayes Lemmerz International, Inc., Huntington, Indiana, Report No. 2004-01-I-IN, September 2005]. Previous studies have shown that aluminum dust explosions are more difficult to suppress with flame retardants or inerting agents than dust explosions fueled by other materials such as coal [A.G. Dastidar, P.R. Amyotte, J. Going, K. Chatrathi, Flammability limits of dust-minimum inerting concentrations, Proc. Saf. Progr., 18-1 (1999) 56-63]. In this paper, an inerting method is discussed to reduce the dust explosion hazard of residue created in an aluminum buffing operation as the residue is generated. This technique reduces the dust explosion hazard throughout the buffing process and within the dust collector systems making the process inherently safer. Dust explosion testing results are presented for process dusts produced during trials with varying amounts of flame retardant additives.

  11. 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.

  12. Surface Modification of Fly Ashes with Carbide Slag and Its Effect on Compressive Strength and Autogenous Shrinkage of Blended Cement Pastes

    Institute of Scientific and Technical Information of China (English)

    HAO Chengwei; DENG Min; MO Liwu; LIU Kaiwei

    2012-01-01

    Surfaces of grade Ⅲ fly ashes were modified through mixing with carbide slag and calcining at 850 ℃ for 1 h.Mineralogical compositions and surface morphology of fly ashes before and after modification were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM),respectively.Effect of surface-modified fly ashes on compressive strength and autogenous shrinkage of blended cement pastes was investigated.Microstructures of cement pastes were examined by backscattered electron (BSE) imaging and mercury intrusion porosimetry (MIP).The experimental results showed that β-C2S was formed on the surfaces of fly ashes after modification.Hydration of β-C2S on the surface-modified fly ashes densified interface zone and enhanced bond strength between particles of fly ashes and hydrated clinkers.In addition,surface modification of fly ashes tended to decrease total porosity and 10-50 nm pores of cement pastes.Surface modification of fly ashes increased compressive strength and reduced autogenous shrinkage of cement pastes.

  13. [Comparison of the psychological effects of standard exercises with those of space exercises in autogenic training: from the perspective of passive concentration].

    Science.gov (United States)

    Kondo, Ikuyo; Koshikawa, Fusako

    2005-08-01

    The purpose of this study was to compare the psychological effects of the heaviness and the warmth Standard Exercises (SE) with those of the first Space Exercises (SP) in Autogenic Training (AT) on college students. This study was conducted by the repeated practice of two experimental groups (SE, SP) and one control group (CT). The participants in the experimental groups practiced once a week, for three weeks. All the participants were assessed with State-Trait Anxiety Inventory-Trait Anxiety (STAI-T), Autogenic Training Clinical Effectiveness Scale (ATCES), and Rosenberg's Self-Esteem Scale. The results showed that the SE group showed more decreases in STAI-T and more increases in ATCES than the SP group, while the more neurotic, showed more increases in self-esteem in both the SE and SP groups. It is possible that non-clinical adults with high neuroticism might be able to enhance their STAI-T and ATCES in the SE group than in the SP group if their SE trainers respected their bodily abilities in readily responding to changes in sensations.

  14. Evaluation of Osteoconductive and Osteogenic Potential of a Dentin-Based Bone Substitute Using a Calvarial Defect Model

    Directory of Open Access Journals (Sweden)

    Ibrahim Hussain

    2012-01-01

    Full Text Available The aim of this study was to assess the osteoconductive and osteogenic properties of processed bovine dentin using a robust rabbit calvarial defect model. In total, 16 New Zealand White rabbits were operated to create three circular defects in the calvaria. One defect was left unfilled, one filled with collected autogenous bone, and the third defect was filled with the dentin-based bone substitute. Following surgery and after a healing period of either 1 or 6 weeks, a CT scan was obtained. Following sacrificing, the tissues were processed for histological examination. The CT data showed the density in the area grafted with the dentin-based material was higher than the surrounding bone and the areas grafted with autologous bone after 1 week and 6 weeks of healing. The area left unfilled remained an empty defect after 1 week and 6 weeks. Histological examination of the defects filled with the dentin product after 6 weeks showed soft tissue encapsulation around the dentin particles. It can be concluded that the rabbit calvarial model used in this study is a robust model for the assessment of bone materials. Bovine dentin is a biostable material; however, it may not be suitable for repairing large 4-wall defects.

  15. Recombinant house dust mite allergens

    OpenAIRE

    2013-01-01

    House dust mites (HDM) are a globally important source of allergen responsible for the sensitization of more than 50% of allergic patients. Specific immunotherapy with HDM extracts is effective but allergen extracts cannot be fully standardized and severe side-effects can occur during the protracted course of treatment. The introduction of molecular biological techniques into allergy research allowed the indentification of more than 20 groups of HDM allergens. Recombinant HDM allergens can be...

  16. Dust amorphization in protoplanetary disks

    CERN Document Server

    Glauser, Adrian M; Watson, Dan M; Henning, Thomas; Schegerer, Alexander A; Wolf, Sebastian; Audard, Marc; Baldovin-Saavedra, Carla

    2009-01-01

    High-energy irradiation of the circumstellar material might impact the structure and the composition of a protoplanetary disk and hence the process of planet formation. In this paper, we present a study on the possible influence of the stellar irradiation, indicated by X-ray emission, on the crystalline structure of the circumstellar dust. The dust crystallinity is measured for 42 class II T Tauri stars in the Taurus star-forming region using a decomposition fit of the 10 micron silicate feature, measured with the Spitzer IRS instrument. Since the sample includes objects with disks of various evolutionary stages, we further confine the target selection, using the age of the objects as a selection parameter. We correlate the X-ray luminosity and the X-ray hardness of the central object with the crystalline mass fraction of the circumstellar dust and find a significant anti-correlation for 20 objects within an age range of approx. 1 to 4.5 Myr. We postulate that X-rays represent the stellar activity and consequ...

  17. The Dust & Gas Properties of M83

    CERN Document Server

    Foyle, K; Mentuch, E; Bendo, G; Dariush, A; Parkin, T; Pohlen, M; Sauvage, M; Smith, M W L; Roussel, H; Baes, M; Boquien, M; Boselli, A; Clements, D L; Cooray, A; Davies, J I; Eales, S A; Madden, S; Page, M J; Spinoglio,

    2012-01-01

    We examine the dust and gas properties of the nearby, barred galaxy M83, which is part of the Very Nearby Galaxy Survey. Using images from the PACS and SPIRE instruments of Herschel, we examine the dust temperature and dust mass surface density distribution. We find that the nuclear, bar and spiral arm regions exhibit higher dust temperatures and masses compared to interarm regions. However, the distribution of dust temperature and mass are not spatially coincident. Assuming a trailing spiral structure, the dust temperature peaks in the spiral arms lie ahead of the dust surface density peaks. The dust mass surface density correlates well with the distribution of molecular gas as traced by CO (J=3-2) images (JCMT) and the star formation rate as traced by H?2 with a correction for obscured star formation using 24 micron emission. Using HI images from THINGS to trace the atomic gas component, we make total gas mass surface density maps and calculate the gas-to-dust ratio. We find a mean gas-to-dust ratio of 84 \\...

  18. Enxerto peritoneal autógeno e fibroplasia: estudo experimental Peritoneum autogenous graft and fibroblast: an experimental study

    Directory of Open Access Journals (Sweden)

    Henrique Celso Silva

    2004-04-01

    Full Text Available OBJETIVO: Avaliar se o enxerto autógeno de peritônio permanece vivo e que tipo de tecido conjuntivo predomina no local. MÉTODO: Foram utilizados 30 ratos machos para o enxerto de um fragmento de peritônio parietal do segmento ântero-superior do abdome, no interior do canal inguinal, fixado com monofilamento. Após 20 dias os animais foram sacrificados, a área doadora reparada e a área do enxerto foram retiradas para estudo histológico á microscopia óptica de luz. Em cinco animais a parede abdominal e o canal inguinal contralateral, sem enxerto, foram utilizados para o estudo de sua anatomia microscópica. RESULTADOS: Houve um predomínio de fibroblastos (células jovens no enxerto, em relação ao receptor e de colágeno denso não modelado em toda a área da intervenção, predominando no receptor, com índice de significância p BACKGROUND: The authors performed a histological investigation of the inguinal canal region which had received an autogenous graft of parietal peritoneum to evaluate if the graft remains alive and what type of conjunctive tissue prevails on the site. METHOD: Thirty male rats received grafts, obtained from a fragment of parietal peritoneum of the anterosuperior segment of the abdomen, into their inguinal canals, which were fixed with monofilaments stiches. Twenty days later the animals were killed, the donor area repaired and the graft area was submited to histological survey through optic light microscopy. In five animals the abdominal wall and the counter lateral inguinal canal without graft were used to surveillance of their microscopy anatomy. RESULTS: There has been a predominance of fibroblast (young cells on the graft in relation to the receiver and of the thick unshaped collagen in the intervention area, with a predominance on the receiver with a p < 0,01 significance index. CONCLUSIONS: The graft stays alive. The histological pattern of the local prevailling conjuctive tissue is the thick unshaped

  19. House dust mites, our intimate associates.

    Science.gov (United States)

    Nadchatram, M

    2005-06-01

    House dust mites have lived in human contact from time immemorial. Human dander or dead skin constitutes the major organic component of the house dust ecosystem. Because the mites feed on dander, dust mites and human association will continue to co-exist as part of our environment. Efficient house-keeping practice is the best form of control to reduce infestation. However, special precautions are important when individuals are susceptible or sensitive to dust mites. House dust mites are responsible for causing asthma, rhinitis and contact dermatitis. The respiratory allergies are caused by the inhalation of dead or live mites, their faecal matter or other byproducts. Immune factors are of paramount importance in the development of dust related or mite induced respiratory diseases. House dust mites were found in some 1,000 samples of dust taken from approximately 330 dwellings in Peninsular Malaysia and Singapore. Mattresses, carpets, corners of a bedroom, and floor beneath the bed are favourable dust mite habitats. The incriminating species based on studies here and elsewhere, as well as many other species of dust mites of unknown etiological importance are widely distributed in Malaysian homes. Density of dust mites in Malaysia and Singapore is greater than in temperate countries. Prevention and control measures with reference to subjects sensitive to dust mite allergies, including chemical control described in studies conducted in Europe and America are discussed. However, a cost free and most practical way to remove mites, their faecal matter and other products is to resort to sunning the bedding and carpets to kill the living mites, and then beaten and brushed to remove the dust and other components.

  20. Metal Dusting-Mechanisms and Preventions

    Institute of Scientific and Technical Information of China (English)

    J.Q.ZHANG; D.J.YOUNG

    2009-01-01

    Metal dusting attacks iron, low and high alloy steels and nickel-or cobalt-base alloys by disintegrating bulk metals and alloys into metal particles in a coke deposit. It occurs in strongly carburising gas atmospheres (carbon activity aC>1) at elevated temperatures (400℃~1000℃). This phenomenon has been studied for decades, but the detailed mechanism is still not well understood. Current methods of protection against metal dusting are either directed to the process conditions-temperature and gas composition-or to the development of a dense adherent oxide layer on the surface of the alloy by selective oxidation. However, metal dusting still occurs by carbon dissolving in the base metal via defects in the oxide scale. The research work at UNSW is aimed at determining the detailed mechanism of metal dusting of both ferritic and austenitic alloys, in particular the microprocesses of graphite deposition, nanoparticle formation and underlying metal destruction. This work was carried out using surface observation, cross-section analysis by focused ion beam and electron microscopic examination of coke deposits at different stages of the reaction. It was found that surface orientation affected carbon deposition and metal dusting at the initial stage of the reaction. Metal dusting occurred only when graphite grew into the metal interior where the volume expansion is responsible for metal disintegration and dusting. It was also found that the metal dusting process could be significantly changed by alterations in alloy chemistry. Germanium was found to affect the iron dusting process by destabilising FeC but increasing the rate of carbon deposition and dusting, which questions the role of cementite in ferritic alloy dusting. Whilst adding copper to iron did not change the carburisation kinetics, cementite formation and coke morphology, copper alloying reduced nickel and nickel-base alloy dusting rates significantly. Application of these fundamental results to the dusting

  1. Regulation of Bone Metabolism.

    Science.gov (United States)

    Shahi, Maryam; Peymani, Amir; Sahmani, Mehdi

    2017-04-01

    Bone is formed through the processes of endochondral and intramembranous ossification. In endochondral ossification primary mesenchymal cells differentiate to chondrocytes and then are progressively substituted by bone, while in intramembranous ossification mesenchymal stem cells (MSCs) differentiate directly into osteoblasts to form bone. The steps of osteogenic proliferation, differentiation, and bone homeostasis are controlled by various markers and signaling pathways. Bone needs to be remodeled to maintain integrity with osteoblasts, which are bone-forming cells, and osteoclasts, which are bone-degrading cells.In this review we considered the major factors and signaling pathways in bone formation; these include fibroblast growth factors (FGFs), bone morphogenetic proteins (BMPs), wingless-type (Wnt) genes, runt-related transcription factor 2 (RUNX2) and osteoblast-specific transcription factor (osterix or OSX).

  2. Regulation of Bone Metabolism

    Science.gov (United States)

    Shahi, Maryam; Peymani, Amir; Sahmani, Mehdi

    2017-01-01

    Bone is formed through the processes of endochondral and intramembranous ossification. In endochondral ossification primary mesenchymal cells differentiate to chondrocytes and then are progressively substituted by bone, while in intramembranous ossification mesenchymal stem cells (MSCs) differentiate directly into osteoblasts to form bone. The steps of osteogenic proliferation, differentiation, and bone homeostasis are controlled by various markers and signaling pathways. Bone needs to be remodeled to maintain integrity with osteoblasts, which are bone-forming cells, and osteoclasts, which are bone-degrading cells.In this review we considered the major factors and signaling pathways in bone formation; these include fibroblast growth factors (FGFs), bone morphogenetic proteins (BMPs), wingless-type (Wnt) genes, runt-related transcription factor 2 (RUNX2) and osteoblast-specific transcription factor (osterix or OSX). PMID:28367467

  3. Aerosol optical absorption by dust and black carbon in Taklimakan Desert, during no-dust and dust-storm conditions

    Institute of Scientific and Technical Information of China (English)

    Hui Lu; Wenshou Wei; Mingzhe Liu; Weidong Gao; Xi Han

    2012-01-01

    Aerosol absorption coefficient σap involves the additive contribution of both black carbon aerosol (BC) and dust aerosol.The linear statistical regression analysis approach introduced by Fialho et al.(2005) is used to estimate the absorption exponents of BC and dust aerosol absorption coefficients,and further to separate the contributions of these two types of aerosols from the total light absorption coefficient measured in the hinterland of Taklimakan Desert in the spring of 2006.Absorption coefficients are measured by means of a 7-wavelength Aethalometer from 1 March to 31 May and from 1 November to 28 December,2006.The absorption exponent of BC absorption coefficient α is estimated as (-0.95 ±0.002) under background weather (supposing the observed absorption coefficient is due only to BC); the estimated absorption exponent of dust aerosol absorption coefficient β during the 6 dust storm periods (strong dust storm) is (-2.55 ± 0.009).Decoupling analysis of the measured light absorption coefficients demonstrates that,on average,the light absorptions caused by dust aerosol and BC make up about 50.5% and 49.5% respectively of the total light absorption at 520 nm; during dust weather process periods (dust storm,floating dust,blowing dust),the contribution of dust aerosol to absorption extinction is 60.6% on average; in the hinterland of desert in spring,dust aerosol is also the major contributor to the total aerosol light absorption,more than that of black carbon aerosol.

  4. A Fractal Model for the Capacitance of Lunar Dust and Lunar Dust Aggregates

    Science.gov (United States)

    Collier, Michael R.; Stubbs, Timothy J.; Keller, John W.; Farrell, William M.; Marshall, John; Richard, Denis Thomas

    2011-01-01

    Lunar dust grains and dust aggregates exhibit clumping, with an uneven mass distribution, as well as features that span many spatial scales. It has been observed that these aggregates display an almost fractal repetition of geometry with scale. Furthermore, lunar dust grains typically have sharp protrusions and jagged features that result from the lack of aeolian weathering (as opposed to space weathering) on the Moon. A perfectly spherical geometry, frequently used as a model for lunar dust grains, has none of these characteristics (although a sphere may be a reasonable proxy for the very smallest grains and some glasses). We present a fractal model for a lunar dust grain or aggregate of grains that reproduces (1) the irregular clumpy nature of lunar dust, (2) the presence of sharp points, and (3) dust features that span multiple scale lengths. We calculate the capacitance of the fractal lunar dust analytically assuming fixed dust mass (i.e. volume) for an arbitrary number of fractal levels and compare the capacitance to that of a non-fractal object with the same volume, surface area, and characteristic width. The fractal capacitance is larger than that of the equivalent non-fractal object suggesting that for a given potential, electrostatic forces on lunar dust grains and aggregates are greater than one might infer from assuming dust grains are sphericaL Consequently, electrostatic transport of lunar dust grains, for example lofting, appears more plausible than might be inferred by calculations based on less realistic assumptions about dust shape and associated capacitance.

  5. Do other components of bedding dust affect sensitisation to house dust mites?

    Science.gov (United States)

    Smith, Claire; Stanley, Thorsten; Crane, Julian; Siebers, Robert

    2011-01-01

    Bedding dust is a mixture of many components, of which the house dust mite (HDM) allergen, Der p 1, is the most allergenic. There has been little work to investigate the effect of other bedding dust components on HDM sensitisation. The objective of the study was to determine the effect of endotoxin in bedding dust on the allergic response in HDM-sensitised individuals. Twenty-nine house dust mite-sensitised adults were skin prick and allergen patch tested against a sterile solution of their own bedding dust and against a solution containing the same concentration of Der p 1 as the bedding solution for comparison. There was no significant difference in wheal size between the diluted house dust mite solution and the bedding dust in spite of their high levels of endotoxin. Symptomatic subjects had larger, but not statistically significant, responses to commercial house dust mite solution than asymptomatic subjects. Allergen patch test responses were negative in 22/29 of subjects using either bedding dust solutions or comparable diluted house dust mite solutions. An individual's own bedding dust does not appear to contain factors that enhance skin prick test or atopy patch test responses to house dust mites.

  6. House dust in seven Danish offices

    Science.gov (United States)

    Mølhave, L.; Schneider, T.; Kjærgaard, S. K.; Larsen, L.; Norn, S.; Jørgensen, O.

    Floor dust from Danish offices was collected and analyzed. The dust was to be used in an exposure experiment. The dust was analyzed to show the composition of the dust which can be a source of airborne dust indoors. About 11 kg of dust from vacuum cleaner bags from seven Danish office buildings with about 1047 occupants (12 751 m 2) was processed according to a standardized procedure yielding 5.5 kg of processed bulk dust. The bulk dust contained 130.000-160.000 CFU g -1 microorganisms and 71.000-90.000 CFU g -1 microfungi. The content of culturable microfungi was 65-123 CFU 30 g -1 dust. The content of endotoxins ranged from 5.06-7.24 EU g -1 (1.45 ng g -1 to 1.01 ng g -1). Allergens (ng g -1) were from 147-159 (Mite), 395-746 (dog) and 103-330 (cat). The macro molecular organic compounds (the MOD-content) varied from 7.8-9.8 mg g -1. The threshold of release of histamine from basophil leukocytes provoked by the bulk dust was between 0.3 and 1.0 mg ml -1. The water content was 2% (WGT) and the organic fraction 33%. 6.5-5.9% (dry) was water soluble. The fiber content was less than 0.2-1.5% (WGT) and the desorbable VOCs was 176-319 μg g -1. Most of the VOC were aldehydes. However, softeners for plastic (DBP and DEHP) were present. The chemical composition includes human and animal skin fragments, paper fibers, glass wool, wood and textilefibers and inorganic and metal particles. The sizes ranged from 0.001-1 mm and the average specific density was 1.0 g m -3. The bulk dust was resuspended and injected into an exposure chamber. The airborne dust was sampled and analyzed to illustrate the exposures that can result from sedimented dirt and dust. The airborne dust resulting from the bulk dust reached concentrations ranging from 0.26-0.75 mg m -3 in average contained 300-170 CFU m -3. The organic fraction was from 55-70% and the water content about 2.5% (WGT). The content of the dust was compared to the similar results reported in the literature and its toxic potency is

  7. Astrophysics of Dust in Cold Clouds

    CERN Document Server

    Draine, B T

    2003-01-01

    Nine lectures reviewing the astrophysics of dust in interstellar clouds. Topics include: (1) Summary of observational evidence concerning interstellar dust: broadband extinction, scattering of starlight, polarization of starlight, spectroscopy of dust, IR and FIR emission, and depletions of grain-forming elements. (2) Optics of interstellar dust grains: dielectric functions of nonconducting and conducting materials, calculational techniques, formulae valid in the Rayleigh limit, Kramers-Kronig relations, microwave emission mechanisms, and X-ray scattering. (3) IR and FIR emission: heating of interstellar dust, including single-photon heating, and resulting IR emission spectrum. (4) Charging of dust grains: collisional charging, photoelectric emission, and resulting charge distribution functions. (5) Dynamics: gas drag, Lorentz force, forces due to anisotropic radiation, and resulting drift velocities. (6) Rotational dynamics: brownian rotation, suprathermal rotation, and effects of starlight torques. (7) Alig...

  8. Lunar Dust and Dusty Plasma Physics

    Science.gov (United States)

    Wilson, Thomas L.

    2009-01-01

    In the plasma and radiation environment of space, small dust grains from the Moon s surface can become charged. This has the consequence that their motion is determined by electromagnetic as well as gravitational forces. The result is a plasma-like condition known as "dusty plasmas" with the consequence that lunar dust can migrate and be transported by magnetic, electric, and gravitational fields into places where heavier, neutral debris cannot. Dust on the Moon can exhibit unusual behavior, being accelerated into orbit by electrostatic surface potentials as blow-off dust, or being swept away by moving magnetic fields like the solar wind as pick-up dust. Hence, lunar dust must necessarily be treated as a dusty plasma subject to the physics of magnetohydrodynamics (MHD). A review of this subject has been given before [1], but a synopsis will be presented here to make it more readily available for lunar scientists.

  9. Dust observations at orbital altitudes surrounding Mars.

    Science.gov (United States)

    Andersson, L; Weber, T D; Malaspina, D; Crary, F; Ergun, R E; Delory, G T; Fowler, C M; Morooka, M W; McEnulty, T; Eriksson, A I; Andrews, D J; Horanyi, M; Collette, A; Yelle, R; Jakosky, B M

    2015-11-01

    Dust is common close to the martian surface, but no known process can lift appreciable concentrations of particles to altitudes above ~150 kilometers. We present observations of dust at altitudes ranging from 150 to above 1000 kilometers by the Langmuir Probe and Wave instrument on the Mars Atmosphere and Volatile Evolution spacecraft. Based on its distribution, we interpret this dust to be interplanetary in origin. A comparison with laboratory measurements indicates that the dust grain size ranges from 1 to 12 micrometers, assuming a typical grain velocity of ~18 kilometers per second. These direct observations of dust entering the martian atmosphere improve our understanding of the sources, sinks, and transport of interplanetary dust throughout the inner solar system and the associated impacts on Mars's atmosphere.

  10. Analysis of reconstruction using non-vascularized iliac bone graft for patients with mandibular defects%非血管化髂骨移植重建下颌骨缺损的临床分析

    Institute of Scientific and Technical Information of China (English)

    谢富强; 孙健

    2012-01-01

    Objective To make a clinical retrospective analysis of reconstruction using autogenous non-vascularized iliac bone graft for patients with mandibular defects, and then to evaluate the treatment effectiveness and operation announcements of this method. Methods 34 patients who were suffered from discontinued mandibule because of tumor or trauma, were treated with autogenous non-vascularized iliac bone graft. The surgery technique, postoperative outcomes and complications were analyzed. Results In 34 patients adopted non-vascularized iliac bone graft, 31 patients adopted rigid internal fixation with titanium mini plate, 3 patients with bridging titanium plate. 27 bone grafts survived completely, the overall success rate was 79.41%. 3(8.82%) of the bone grafts healed after infection, 4(11.76%) bone grafts lost because of infection. Conclusion The autogenous non-vascularized iliac bone graft is one of the most important way for the reconstruction of mandibular defects. The methods of internal fixation includes titanium mini pate and bridging titanium plate.%目的 对非血管化髂骨移植重建下颌骨缺损的病例进行临床回顾性分析,探讨其治疗效果及手术注意事项.方法 选择因肿瘤和外伤致下颌骨缺损后行自体非血管化髂骨同期移植重建术修复的34例患者为研究对象,分析其手术方法、术后效果及并发症的发生情况.结果 采用游离非血管化髂骨同期移植重建下颌骨缺损的34例患者中,小钛板双排内固定31例,重建板内固定3例.34例患者中,成功病例27例(79.41%),良好病例3例(8.82%),失败病例4例(11.76%).失败原因均为感染而取出植入骨.结论 自体非血管化髂骨移植重建术是下颌骨缺损重建的重要方法之一,内固定的方式有小钛板和重建板.

  11. CRADE OF SAND AND DUST STORM WEATHER

    Institute of Scientific and Technical Information of China (English)

    Niu Ruoyun; Tian Cuiying; Bi Baogui; Yang Keming; Wang Youheng; Tuo Ya; Ding Haifang; Zhang Tairen

    2011-01-01

    Background Sand and dust storm,as one of the main disastrous weathers that affect northern China,not only affect the people health and normal life,but cause the short-term climatic changes due to the direct and indirect radiation of the earth-atmosphere system through the dust floating in the sky.The sand end dust weather and its potential harm on the national economy,ecological environment,social activities and other aspects have aroused worldwide concern.

  12. [The preparation and characterization of fine dusts carried out in the Clinica del Lavoro di Milano in support of experimental studies].

    Science.gov (United States)

    Occella, E; Maddalon, G; Peruzzo, G F; Foà, V

    1999-01-01

    pestles and rotating drum mills with autogenic grinding load were used for grinding: the size of the treated samples was reduced to 0.05 mm and an extremely fine fraction was extracted, smaller than 7-10 microns, which was used for pneumoconioses research. The characterization of the dust produced was in any case achieved by means of preliminary examination under the optical microscope (polarized light, sometimes supplemented with phase contrast), followed by quantitative analysis using chemical/petrographic, chemical diffraction or, more commonly, petrographic/diffraction techniques. Microscopic examination, if necessary supplemented with photo-micrography, was also used for particle size control, for numerical counting and subsequent reference to weight proportion. For all operational procedures the essential data on instruments and methods are reported. During studies on production, separation of fine dusts and their characterization, partly performed with support from the European Community (EEC/European Coal and Steel Commission), the following topics in particular were addressed: connections between particle size and free silica content in the measurable dust size fraction of the grinding products and in airborne dusts; characteristics of the dusts and risk indices in Italian iron and pyrite mines; possibility of abatement of the ultrafine classes of airborne dusts in pneumatically filled stopes by the addition of salts; comparison of the latest dust selectors used within the European Community; influence of the grinding methods on the results of fibrous and soft mineral measurement using X-ray diffraction analysis.

  13. Propagation of dust-acoustic waves in weakly ionized plasmas with dust-charge fluctuation

    Indian Academy of Sciences (India)

    K K Mondal

    2004-11-01

    For an unmagnetized partially ionized dusty plasma containing electrons, singly charged positive ions, micron-sized massive negatively charged dust grains and a fraction of neutral atoms, dispersion relations for both the dust-ion-acoustic and the dust-acoustic waves have been derived, incorporating dust charge fluctuation. The dispersion relations, under various conditions, have been exhaustively analysed. The explicit expressions for the growth rates have also been derived.

  14. Characterization of the inflammatory response to four commercial bone graft substitutes using a murine biocompatibility model

    Directory of Open Access Journals (Sweden)

    Markel DC

    2012-01-01

    Full Text Available David C Markel1, S Trent Guthrie2, Bin Wu3, Zheng Song4, Paul H Wooley41Department of Orthopaedics, Providence Hospital and Medical Centers, Southfield, MI, 2Henry Ford Hospital, Detroit, MI, 3Department of Biomedical Engineering, Wayne State University, Detroit, MI, 4Orthopaedic Research Institute, Wichita, KS, USAAbstract: Bone grafting is utilized in nearly all orthopedic subspecialties and in most anatomic regions. Bone graft substitutes have the potential to offer similar efficacy as autogenous grafts without the morbidity of harvest. Several studies have noted the efficacy of new-generation bone substitute products, but few studies have evaluated their safety. This study characterizes and quantifies the inflammatory reaction to four different commercially available bone graft substitutes, which were examined using the in vivo murine air pouch biocompatibility model. One coralline hydroxyapatite product was chosen as an example of a purely osteoconductive material. Three demineralized bone matrix products were chosen to represent products that are both osteoconductive and osteoinductive. Samples were implanted in a murine air pouch and harvested after 14 days in situ. Pouch fluid was extracted, mRNA isolated, and reverse transcription polymerase chain reactions carried out to detect interleukin-1 gene expression as a marker for inflammation. In addition, multiple histological characteristics were examined to quantify cellular responses to the implanted materials. All bone graft substitutes induced a significant inflammatory response compared with negative controls. Histology and polymerase chain reaction data indicated that the level of inflammatory reaction was elevated in materials with a higher demineralized bone matrix to carrier proportion. The hydroxyapatite product generated a low inflammatory reaction. In conclusion, this study used an in vivo model of biocompatibility to demonstrate that a significant inflammatory reaction occurs

  15. Dust Devils and Convective Vortices on Mars

    Science.gov (United States)

    Ordonez-Etxeberria, I.; Hueso, R.; Sánchez-Lavega, A.

    2017-03-01

    Dust devils are low pressure convective vortices able to lift dust from the surface of a planet. They are a common feature on Mars and they can also be found on desertic locations on Earth. On Mars they are considered an important part of the atmospheric dust cycle. Dust in Mars is an essential ingredient of the atmosphere where it affects the radiative balance of the planet. Here we review observations of these dusty vortices from orbit, from in situ measurements on the surface of Mars and some of the models developed to simulate them.

  16. Dust grains from the heart of supernovae

    Science.gov (United States)

    Bocchio, Marco; Marassi, Stefania; Schneider, Raffaella; Bianchi, Simone; Limongi, Marco; Chieffi, A.

    2016-06-01

    Dust grains are classically thought to form in the winds of asymptotic giant branch (AGB) stars. However, there is increasing evidence today for dust formation in supernovae (SNe). To establish the relative importance of these two classes of stellar sources of dust, it is important to know the fraction of freshly formed dust in SN ejecta that is able to survive the passage of the reverse shock and be injected in the interstellar medium. We have developed a new code (GRASH_Rev) which follows the newly-formed dust evolution throughout the supernova explosion until the merging of the forward shock with the circumstellar ISM. We have considered four well studied SNe in the Milky Way and Large Magellanic Cloud: SN1987A, CasA, the Crab Nebula, and N49. For all the simulated models, we find good agreement with observations and estimate that between 1 and 8% of the observed mass will survive, leading to a SN dust production rate of (3.9± 3.7)×10^(-4) MM_{⊙})/yr in the Milky Way. This value is one order of magnitude larger than the dust production rate by AGB stars but insufficient to counterbalance the dust destruction by SNe, therefore requiring dust accretion in the gas phase.

  17. Halo dust detection around NGC 891

    CERN Document Server

    Bocchio, M; Hunt, L K; Schneider, R

    2015-01-01

    Observations of edge-on galaxies allow us to investigate the vertical extent and properties of dust, gas and stellar distributions. NGC 891 has been studied for decades and represents one of the best studied cases of an edge-on galaxy. We use deep PACS data together with IRAC, MIPS and SPIRE data to study the vertical extent of dust emission around NGC 891. We also test the presence of a more extended, thick dust component. By performing a convolution of an intrinsic vertical profile emission with each instrument PSF and comparing it with observations we derived the scaleheight of a thin and thick dust disc component. For all wavelengths considered the emission is best fit with the sum of a thin and a thick dust component. The scaleheight of both dust components shows a gradient passing from 70 $\\mu$m to 250 $\\mu$m. This could be due to a drop in dust heating (and thus dust temperature) with the distance from the plane, or to a sizable contribution ($\\sim 15 - 80%$) of an unresolved thin disc of hotter dust t...

  18. On the Feasibility of Utilizing Allogeneic Bone Blocks for Atrophic Maxillary Augmentation

    Directory of Open Access Journals (Sweden)

    Alberto Monje

    2014-01-01

    Full Text Available Purpose. This systematic review was aimed at assessing the feasibility by means of survival rate, histologic analysis, and causes of failure of allogeneic block grafts for augmenting the atrophic maxilla. Material and Methods. A literature search was conducted by one reviewer in several databases. Articles were included in this systematic review if they were human clinical trials in which outcomes of allogeneic bone block grafts were studied by means of survival rate. In addition other factors were extracted in order to assess their influence upon graft failure. Results. Fifteen articles fulfilled the inclusion criteria and subsequently were analyzed in this systematic review. A total of 361 block grafts could be followed 4 to 9 months after the surgery, of which 9 (2.4% failed within 1 month to 2 months after the surgery. Additionally, a weighed mean 4.79 mm (95% CI: 4.51–5.08 horizontal bone gain was computed from 119 grafted sites in 5 studies. Regarding implant cumulative survival rate, the weighed mean was 96.9% (95% CI: 92.8–98.7%, computed from 228 implants over a mean follow-up period of 23.9 months. Histologic analysis showed that allogeneic block grafts behave differently in the early stages of healing when compared to autogenous block grafts. Conclusion. Atrophied maxillary reconstruction with allogeneic bone block grafts represents a reliable option as shown by low block graft failure rate, minimal resorption, and high implant survival rate.

  19. Effect of nonthermal ion distribution and dust temperature on nonlinear dust-acoustic solitary waves

    Indian Academy of Sciences (India)

    K Annou; R Annou

    2012-01-01

    Dust-acoustic solitary waves in unmagnetized dusty plasma whose constituents are inertial charged dust grains, Boltzmannian electrons and nonthermal ions have been investigated by taking into account finite dust temperature. The pseudopotential has been used to study solitary solution. The existence of solitary waves having negative potential is reported.

  20. What Is Bone Cancer?

    Science.gov (United States)

    ... start in bone, muscle, fibrous tissue, blood vessels, fat tissue, as well as some other tissues. They can develop anywhere in the body. There are several different types of bone tumors. Their names are based on ...

  1. Osteochondroma (Bone Tumor)

    Science.gov (United States)

    ... to be the most common benign bone tumor, accounting for 35% to 40% of all benign bone ... imaging scans. Doctors may also request computed tomography (CT) scans or magnetic resonance imaging (MRI) scans to ...

  2. What causes bone loss?

    Science.gov (United States)

    ... bone biology. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology . 13th ed. Philadelphia, PA: Elsevier; 2016:chap 29. Maes C, Kronenberg HM. Bone development and remodeling. In: Jameson JL, ...

  3. 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 ( ...

  4. Supernova olivine from cometary dust

    Science.gov (United States)

    Messenger, Scott; Keller, Lindsay P.; Lauretta, Dante S.

    2005-01-01

    An interplanetary dust particle contains a submicrometer crystalline silicate aggregate of probable supernova origin. The grain has a pronounced enrichment in 18O/16O (13 times the solar value) and depletions in 17O/16O (one-third solar) and 29Si/28Si (olivine (forsterite 83) grains olivine grain could have formed by equilibrium condensation from cooling supernova ejecta if several different nucleosynthetic zones mixed in the proper proportions. The supernova grain is also partially encased in nitrogen-15-rich organic matter that likely formed in a presolar cold molecular cloud.

  5. Carbon petrology in cometary dust

    Science.gov (United States)

    Rietmeijer, Frans J. M.

    1992-01-01

    Chondritic porous (CP) interplanetary dust particles (IDP's) are collected in the Earth's stratosphere. There exists an extensive database on major and minor element chemistry, stable isotopes, noble gas abundances and mineralogy of many CP IDP's, as well as infrared and Raman spectroscopic properties. For details on the mineralogy, chemistry and physical properties of IDP's, I refer to the reviews by Mackinnon and Rietmeijer (1987), Bradley et al. (1988) and Sandford (1987). Texture, mineralogy (Mackinnon and Rietmeijer, 1987) and chemistry (Schramm et al., 1989; Flynn and Sutton, 1991) support the notion that CP IDP's are a unique group of ultrafine-grained extraterrestiral materials that are distinct from any known meteorite class. Their fluffy, or porous, morphology suggests that CP IDP's probably endured minimal alteration by protoplanetary processes since their formation. It is generally accepted that CP IDP's are solid debris from short-period comets. The evidence is mostly circumstantial but this notion gained significant support based on the comet Halley dust data (Brownlee, 1990). In this paper, I will accept that CP IDP's are indeed cometary dust. The C/Si ratio in CP IDP's is 3.3 times higher than in CI carbonaceous chondrites (Schramm et al. 1989). The intraparticle carbon distribution is heteorogeneous (Rietmeijer and McKay, 1986). Carbon occurs both in oxidized and reduced forms. Analytical electron microscope (AEM) and Raman spectroscopic analyses have shown the presence of several carbon forms in CP IDP's but the data are scattered in the literature. Carbons in cometary CP IDP's are among the most pristine Solar System carbons available for laboratory study. Similar to a recently developed petrological model for the diversity of layer silicates in CP IDP's (Zolensky, 1991) that is useful to constrain in situ aqueous alteration in comets (Rietmeijer and Mackinnon, 1987a), I here present the first effort to develop a petrological concept of carbons

  6. Androgens and bone.

    Science.gov (United States)

    Vanderschueren, Dirk; Vandenput, Liesbeth; Boonen, Steven; Lindberg, Marie K; Bouillon, Roger; Ohlsson, Claes

    2004-06-01

    Loss of estrogens or androgens increases the rate of bone remodeling by removing restraining effects on osteoblastogenesis and osteoclastogenesis, and also causes a focal imbalance between resorption and formation by prolonging the lifespan of osteoclasts and shortening the lifespan of osteoblasts. Conversely, androgens, as well as estrogens, maintain cancellous bone mass and integrity, regardless of age or sex. Although androgens, via the androgen receptor (AR), and estrogens, via the estrogen receptors (ERs), can exert these effects, their relative contribution remains uncertain. Recent studies suggest that androgen action on cancellous bone depends on (local) aromatization of androgens into estrogens. However, at least in rodents, androgen action on cancellous bone can be directly mediated via AR activation, even in the absence of ERs. Androgens also increase cortical bone size via stimulation of both longitudinal and radial growth. First, androgens, like estrogens, have a biphasic effect on endochondral bone formation: at the start of puberty, sex steroids stimulate endochondral bone formation, whereas they induce epiphyseal closure at the end of puberty. Androgen action on the growth plate is, however, clearly mediated via aromatization in estrogens and interaction with ERalpha. Androgens increase radial growth, whereas estrogens decrease periosteal bone formation. This effect of androgens may be important because bone strength in males seems to be determined by relatively higher periosteal bone formation and, therefore, greater bone dimensions, relative to muscle mass at older age. Experiments in mice again suggest that both the AR and ERalpha pathways are involved in androgen action on radial bone growth. ERbeta may mediate growth-limiting effects of estrogens in the female but does not seem to be involved in the regulation of bone size in males. In conclusion, androgens may protect men against osteoporosis via maintenance of cancellous bone mass and

  7. 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.)

  8. 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...

  9. Desert dust hazards: A global review

    Science.gov (United States)

    Middleton, N. J.

    2017-02-01

    Dust storms originate in many of the world's drylands and frequently present hazards to human society, both within the drylands themselves but also outside drylands due to long-range transport of aeolian sediments. Major sources of desert dust include the Sahara, the Middle East, central and eastern Asia, and parts of Australia, but dust-raising occurs all across the global drylands and, on occasion, beyond. Dust storms occur throughout the year and they vary in frequency and intensity over a number of timescales. Long-range transport of desert dust typically takes place along seasonal transport paths. Desert dust hazards are here reviewed according to the three phases of the wind erosion system: where dust is entrained, during the transport phase, and on deposition. This paper presents a synthesis of these hazards. It draws on empirical examples in physical geography, medical geology and geomorphology to discuss case studies from all over the world and in various fields. These include accelerated soil erosion in agricultural zones - where dust storms represent a severe form of accelerated soil erosion - the health effects of air pollution caused by desert aerosols via their physical, chemical and biological properties, transport accidents caused by poor visibility during desert dust events, and impacts on electricity generation and distribution. Given the importance of desert dust as a hazard to human societies, it is surprising to note that there have been relatively few attempts to assess their impact in economic terms. Existing studies in this regard are also reviewed, but the wide range of impacts discussed in this paper indicates that desert dust storms deserve more attention in this respect.

  10. Perchlorate in dust fall and indoor dust in Malta: An effect of fireworks.

    Science.gov (United States)

    Vella, Alfred J; Chircop, Cynthia; Micallef, Tamara; Pace, Colette

    2015-07-15

    We report on the presence of perchlorate in the settleable dust of Malta, a small central Mediterranean island. Both dust fall collected directly as it precipitated from atmosphere over a period of one month and deposited indoor dust from domestic residences were studied. Perchlorate was determined by ion chromatography of water extracts of the collected dusts. Dust fall was collected from 43 towns during 2011 to 2013 and indoor dust was sampled from homes in the same localities. Perchlorate was detected in 108 of 153 samples of dust fall (71%) and in 28 of 37 indoor dust samples (76%). Detectable perchlorate in dust fall ranged from 0.52μgg(-1) to 561μgg(-1) with a median value of 6.2μgg(-1); in indoor dust, levels were from 0.79μgg(-1) to 53μgg(-1) with a median value of 7.8μgg(-1), the highest recorded anywhere to date. Statistical analysis suggested that there was no significant difference in perchlorate content of indoor dust and dust fall. Perchlorate levels in dust fall escalate during the summer in response to numerous religious feasts celebrated with fireworks and perchlorate persists at low μgg(-1) concentrations for several months beyond the summer festive period. In Malta, perchlorate derives exclusively from KClO4, imported for fireworks manufacture. Its residue in dust presents an exposure risk to the population, especially via ingestion by hand to mouth transfer. Our results suggest that wherever intensive burning of fireworks takes place, the environmental impact may be much longer lived than realised, mainly due to re-suspension and deposition of contaminated settled dust in the urban environment.

  11. eblur/dust: a modular python approach for dust extinction and scattering

    Science.gov (United States)

    Corrales, Lia

    2016-03-01

    I will present a library of python codes -- github.com/eblur/dust -- which calculate dust scattering and extinction properties from the IR to the X-ray. The modular interface allows for custom defined dust grain size distributions, optical constants, and scattering physics. These codes are currently undergoing a major overhaul to include multiple scattering effects, parallel processing, parameterized grain size distributions beyond power law, and optical constants for different grain compositions. I use eblur/dust primarily to study dust scattering images in the X-ray, but they may be extended to applications at other wavelengths.

  12. Dust Charging in Electronegative SiH4 Plasmas

    Institute of Scientific and Technical Information of China (English)

    DUAN Ping; WANG Zheng-Xiong; LIU Yue; LIU Jin-Yuan; WANG Xiao-Gang

    2005-01-01

    @@ We theoretically investigate the dust charging in electronegative silane (SiH4) plasmas, taking into account the effects of UV photodetachment. It is found that UV photodetachment could significantly lower the dust negative charge and even makes dust grains be positively charged under some special conditions. In addition, the other parameters, involving the negative ion and dust number densities, electron temperature and dust radius, have great effects upon the dust charging.

  13. Oxytocin and bone

    Science.gov (United States)

    Sun, Li; Zaidi, Mone; Zallone, Alberta

    2014-01-01

    One of the most meaningful results recently achieved in bone research has been to reveal that the pituitary hormones have profound effect on bone, so that the pituitary-bone axis has become one of the major topics in skeletal physiology. Here, we discuss the relevant evidence about the posterior pituitary hormone oxytocin (OT), previously thought to exclusively regulate parturition and breastfeeding, which has recently been established to directly regulate bone mass. Both osteoblasts and osteoclasts express OT receptors (OTR), whose stimulation enhances bone mass. Consistent with this, mice deficient in OT or OTR display profoundly impaired bone formation. In contrast, bone resorption remains unaffected in OT deficiency because, even while OT stimulates the genesis of osteoclasts, it inhibits their resorptive function. Furthermore, in addition to its origin from the pituitary, OT is also produced by bone marrow osteoblasts acting as paracrine-autocrine regulator of bone formation modulated by estrogens. In turn, the power of estrogen to increase bone mass is OTR-dependent. Therefore, OTR−/− mice injected with 17β-estradiol do not show any effects on bone formation parameters, while the same treatment increases bone mass in wild-type mice. These findings together provide evidence for an anabolic action of OT in regulating bone mass and suggest that bone marrow OT may enhance the bone-forming action of estrogen through an autocrine circuit. This established new physiological role for OT in the maintenance of skeletal integrity further suggests the potential use of this hormone for the treatment of osteoporosis. PMID:25209411

  14. Galaxy Zoo: Dust in Spirals

    CERN Document Server

    Masters, Karen L; Bamford, Steven; Mosleh, Moein; Lintott, Chris J; Andreescu, Dan; Edmondson, Edward M; Keel, William C; Murray, Phil; Raddick, M Jordan; Schawinski, Kevin; Slosar, Anze; Szalay, Alexander S; Thomas, Daniel; Vandenberg, Jan

    2010-01-01

    We investigate the effect of dust on spiral galaxies by measuring the inclination-dependence of optical colours for 24,276 well-resolved SDSS galaxies visually classified in Galaxy Zoo. We find clear trends of reddening with inclination which imply a total extinction from face-on to edge-on of 0.7, 0.6, 0.5 and 0.4 magnitudes for the ugri passbands. We split the sample into "bulgy" (early-type) and "disky" (late-type) spirals using the SDSS fracdeV (or f_DeV) parameter and show that the average face-on colour of "bulgy" spirals is redder than the average edge-on colour of "disky" spirals. This shows that the observed optical colour of a spiral galaxy is determined almost equally by the spiral type (via the bulge-disk ratio and stellar populations), and reddening due to dust. We find that both luminosity and spiral type affect the total amount of extinction, with "disky" spirals at M_r ~ -21.5 mags having the most reddening. This decrease of reddening for the most luminous spirals has not been observed before ...

  15. House Dust Mite Respiratory Allergy

    DEFF Research Database (Denmark)

    Calderón, Moisés A; Kleine-Tebbe, Jörg; Linneberg, Allan

    2015-01-01

    Although house dust mite (HDM) allergy is a major cause of respiratory allergic disease, specific diagnosis and effective treatment both present unresolved challenges. Guidelines for the treatment of allergic rhinitis and asthma are well supported in the literature, but specific evidence on the e......Although house dust mite (HDM) allergy is a major cause of respiratory allergic disease, specific diagnosis and effective treatment both present unresolved challenges. Guidelines for the treatment of allergic rhinitis and asthma are well supported in the literature, but specific evidence...... of specific IgE testing, but availability is limited. Treatment options for HDM allergy are limited and include HDM avoidance, which is widely recommended as a strategy, although evidence for its efficacy is variable. Clinical efficacy of pharmacotherapy is well documented; however, symptom relief does...... not extend beyond the end of treatment. Finally, allergen immunotherapy has a poor but improving evidence base (notably on sublingual tablets) and its benefits last after treatment ends. This review identifies needs for deeper physician knowledge on the extent and impact of HDM allergy in respiratory disease...

  16. Dust tori in radio galaxies

    CERN Document Server

    van der Wolk, G; Peletier, R F; Pel, J W

    2009-01-01

    We investigate the validity of the quasar - radio galaxy unification scenario and determine the presence of dust tori among radio galaxies of various types. Actively accreting supermassive black holes in the centres of radio galaxies may be uncovered through their dust tori reradiating the optical and ultraviolet continuum in mid-infrared bands. Using VISIR on the VLT, we have obtained sub-arcsecond (~0.40") resolution N-band images, at a wavelength of 11.85 micron, of the nuclei of a sample of 27 radio galaxies of four types in the redshift range z=0.006-0.156. The sample consists of 8 edge-darkened, low-power Fanaroff-Riley class I (FR-I) radio galaxies, 6 edge-brightened, class II (FR-II) radio galaxies displaying low-excitation optical emission, 7 FR-IIs displaying high-excitation optical emission, and 6 FR-II broad emission line radio galaxies. Out of the sample of 27 objects, 10 nuclei are detected and several have constraining non-detections at 10 sigma sensitivities of 7 mJy. On the basis of the core ...

  17. Dust polarization and ISM turbulence

    CERN Document Server

    Caldwell, Robert R; Kamionkowski, Marc

    2016-01-01

    Perhaps the most intriguing result of Planck's dust-polarization measurements is the observation that the power in the E-mode polarization is twice that in the B mode, as opposed to pre-Planck expectations of roughly equal dust powers in E and B modes. Here we show how the E- and B-mode powers depend on the detailed properties of the fluctuations in the magnetized interstellar medium. These fluctuations are classified into the slow, fast, and Alfv\\'en magnetohydrodynamic (MHD) waves, which are determined once the ratio of gas to magnetic-field pressures is specified. We also parametrize models in terms of the power amplitudes and power anisotropies for the three types of waves. We find that the observed EE/BB ratio (and its scale invariance) and positive TE correlation cannot be easily explained in terms of favored models for MHD turbulence. The observed power-law index for temperature/polarization fluctuations also disfavors MHD turbulence. We thus speculate that the 0.1--30 pc length scales probed by these ...

  18. Effect of bone marrow and low power lasers on fracture healing with destruction of both periosteum and endosteum in rabbits

    Directory of Open Access Journals (Sweden)

    M. G. Thanoon

    2010-01-01

    Full Text Available Ten mature rabbits of local breed were used in this study; weighing between 1.5 to 1.75 kg and aged about 1–2 years. These animals were divided into two equal groups; in group A destruction of both periosteum and endosteum was done one centimeter from each side of mid-shaft femoral bone fracture, then sufficient amount of autogenously bone marrow was injected directly at the fracture site after immobilization by intramedullary pin. In group B a similar procedure was achieved as in group A, but in additional to that He-Ne infrared laser therapy was used for several sessions. The result of radiological findings indicated that, the fracture healing occurred within group B at fifteen weeks, whereas in group A the healing occurred at eighteen weeks after operation. The implantation of autologous bone marrow enhanced the fracture healing, whereas using of combinations of autologous bone marrow and He-Ne infrared laser therapy hastened the healing.

  19. Wind modeling of Chihuahuan Desert dust outbreaks

    Science.gov (United States)

    Rivera Rivera, Nancy I.; Gill, Thomas E.; Gebhart, Kristi A.; Hand, Jennifer L.; Bleiweiss, Max P.; Fitzgerald, Rosa M.

    The Chihuahuan Desert region of North America is a significant source of mineral aerosols in the Western Hemisphere, and Chihuahuan Desert dust storms frequently impact the Paso del Norte (El Paso, USA/Ciudad Juarez, Mexico) metropolitan area. A statistical analysis of HYSPLIT back trajectory residence times evaluated airflow into El Paso on all days and on days with synoptic (non-convective) dust events in 2001-2005. The incremental probability—a measure of the areas most likely to have been traversed by air masses arriving at El Paso during dusty days—was only strongly positively associated with the region west-southwest of the city, a zone of known dust source areas. Focused case studies were made of major dust events on 15 April and 15 December 2003. Trajectories approached the surface and MM5 (NCAR/Penn State Mesoscale Model) wind speeds increased at locations consistent with dust sources observed in satellite imagery on those dates. Back trajectory and model analyses suggested that surface cyclones adjacent to the Chihuahuan Desert were associated with the extreme dust events, consistent with previous studies of dust storms in the Southern High Plains to the northeast. The recognition of these meteorological patterns serves as a forecast aid for prediction of dust events likely to impact the Paso del Norte.

  20. Airborne microorganisms and dust from livestock houses

    NARCIS (Netherlands)

    Zhao, Y.; Aarnink, A.J.A.; Jong, de M.C.M.; Groot Koerkamp, P.W.G.

    2011-01-01

    The objective of this study was to evaluate the efficiencies and suitability of samplers for airborne microorganisms and dust, which could be used in practical livestock houses. Two studies were performed: 1) Testing impaction and cyclone pre-separators for dust sampling in livestock houses; 2) Dete

  1. 30 CFR 56.9315 - Dust control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Dust control. 56.9315 Section 56.9315 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... control. Dust shall be controlled at muck piles, material transfer points, crushers, and on haulage...

  2. Design and Implementation of Space Dust Database

    Institute of Scientific and Technical Information of China (English)

    左维; 李春来; 徐琳; 刘剑; 刘建军

    2004-01-01

    Space debris is very dangerous to the security of on-the-orbit spacecrafts, and it is increasing in number at high speed with the expansion of human space exploration. Space debris has become a serious space pollutant noticed by many astronomers. The increase of space dust sources and the development of research on space dust urgently need space dust data sharing and exchanging. It is necessary for us to establish the Space Dust Database to realize the sharing and canonical management of the data. The Space Dust Database (SDD) management system, based on the 3-layer B/S computer mode, was designed and implemented in this paper. The system's features include significantly improved runtime efficiency, good scalability and maintainability. The Space Dust Database can provide some scientific bases for the study of the chemical constituents, mineral composition, origin and sources of space dust, but also provide excellent data services and decision-making support for the protection of space and model construction of space dust.

  3. Dust Dynamics in Kelvin-Helmholtz Instabilities

    Science.gov (United States)

    Hendrix, Tom; Keppens, Rony

    2013-04-01

    The Kelvin-Helmholtz instability (KHI) is a fluid instability which arises when two contacting flows have different tangential velocities. As shearing flows are very common in all sorts of (astro)physical fluid setups, the KHI is frequently encountered. In many astrophysical fluids the gas fluid in loaded with additional dust particles. Here we study the influence of these dust particles on the initiation of the KHI, as well as the effect the KHI has on the density distribution of dust species in a range of different particle sizes. This redistribution by the instability is of importance in the formation of dust structures in astrophysical fluids. To study the effect of dust on the linear and nonlinear phase of the KHI, we use the multi-fluid dust + gas module of the MPI-AMRVAC [1] code to perform 2D and 3D simulations of KHI in setups with physical quantities relevant to astrophysical fluids. A clear dependency on dust sizes is seen, with larger dust particles displaying significantly more clumping than smaller ones.

  4. Mechanical properties of dust collected by dust separators in iron ore sinter plants.

    Science.gov (United States)

    Lanzerstorfer, Christof

    2015-01-01

    The flow-related mechanical properties of dusts from the de-dusting systems of several sinter plants were investigated. The mass median diameters of the dusts were in the range from approximately 3 to 100 µm. Also, the bulk density of the dusts varied in a wide range (approximately 400 to 2300 kg/m³). A good correlation between the bulk density and the mass median diameter for most of the dusts was found. In contrast, the angles of repose did not vary very much, only for the coarsest dust a significantly lower value was measured. The angles of internal friction as well as the wall friction angles were lower for coarse dust and higher for fine dust. The shear tests showed that both angles depend considerably on the stress level. At low stress, the angles decreased significantly with increasing values of stress, whereas at higher stress, the dependence was small or even disappeared. The only exception to this behaviour was shown by the finest dust. The flowability decreased with the particle size. The flowability categories suggested by the three flowability indicators were passable only for the coarser dusts. For the finer dusts, the flowability was overestimated by all flowability indicators.

  5. 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.)

  6. Autogenous orbital reconstruction in a child with congenital abnormalities of the orbital roof and vertical orbital dystopia.

    Science.gov (United States)

    Moore, Forrest O; Thornton, Brian P; Zabel, David D; Vasconez, Henry C

    2004-11-01

    Congenital anomalies of the orbital roof are rare occurrences. The case of a 2-year-old child with vertical orbital dystopia and abnormalities of the right bony orbit is presented. The patient underwent right orbital reconstruction to restore facial symmetry. A coronal approach with a frontal craniotomy was used for intracranial exposure. The abnormal angulation of the roof was corrected, and the defect was reconstructed with a split-calvarial bone graft harvested from the parietal region. The bone graft was secured with resorbable plate fixation. To preserve vision, reconstruction of this type must be done at an early age, preferably before the age of 4 years. In this patient, there is good facial symmetry and normal globe positioning 5 years after surgery.

  7. Application of autogenous artery to repair parotid duct defect%自体动脉在腮腺导管重建中的应用

    Institute of Scientific and Technical Information of China (English)

    池宇峰; 王维; 谭锡涛

    2013-01-01

    目的:利用自体动脉重建腮腺导管缺损,并探讨其临床效果.方法:用硬膜外麻醉导管做支架,截取一段颞浅动脉,重建缺损的腮腺导管;术后1个月、3个月、半年、1年复诊,检查患者腮腺局部有无肿胀、涎瘘,导管是否通畅.结果:6例患者腮腺局部无肿胀,无涎瘘,腮腺导管通畅,腮腺分泌功能正常.结论:以硬膜外麻醉导管做支架,采用自体动脉重建腮腺导管缺损效果良好.%PURPOSE:To use autogenous artery to repair parotid duct defect,and to investigate the clinical effect.METHODS:Anesthesia epidural catheter was used to support the parotid duct and a segment of superficial temporal artery was harvested to reconstruct the defect of the parotid duct.The patients were asked to revisit 1 month,3 months,half a year and one year postoperatively.RESULTS:No swelling and salivary fistula was noted.The parotid ducts were successfully reconstructed with good patency and normal secretion.CONCLUSIONS:Using anesthesia epidural catheter to support the parotid duct,autogenous artery is excellent for repair of parotid duct defect.

  8. Argus II retinal prosthesis implantation with scleral flap and autogenous temporalis fascia as alternative patch graft material: a 4-year follow-up

    Science.gov (United States)

    Matet, Alexandre; Amar, Nawel; Mohand-Said, Saddek; Sahel, José-Alain; Barale, Pierre-Olivier

    2016-01-01

    Introduction The Argus II retinal prosthesis is composed of an epiretinal electrode array positioned over the macula and connected to an extrascleral electronics case via a silicone cable, running through a sclerotomy. During implantation, the manufacturer recommends to cover the sclerotomy site with a patch of processed human pericardium to prevent postoperative hypotony and conjunctival erosion by the underlying electronics case. Due to biomedical regulations prohibiting the use of this material in France, we developed an alternative technique combining a scleral flap protecting the sclerotomy and an autogenous graft of superior temporalis fascia overlying the electronics case. Methods The purpose of this study is to describe the 4-year outcomes of this modified procedure in three subjects who underwent Argus II Retinal Prosthesis System implantation. Clinical data consisting of intraocular pressure measurements and tolerance in terms of conjunctival erosion or inflammation were retrospectively assessed over a 4-year postoperative follow-up. Results None of the three patients implanted with the modified technique developed ocular hypotony over 4 years. A normal, transient conjunctival inflammation occurred during the first postoperative month but conjunctival erosion was not observed in any of the three patients over 4 years. Four years after implantation, the autogenous temporalis fascia graft remained well tolerated and the retinal prosthesis was functional in all three patients. Conclusion The combination of an autograft of superficial temporalis fascia and a scleral flap efficiently prevented leakage through the sclerotomy site, ocular hypotony, and conjunctival erosion by the extrascleral electronics case. This modified technique is suitable for the implantation of existing and forthcoming retinal prostheses. Superficial temporalis fascia may also be used as alternative to commercial tectonic tissues for scleral wound repair in clinical settings where they

  9. Inorganic analysis of dust fall and office dust in an industrial area of Jordan.

    Science.gov (United States)

    Jaradat, Qasem M; Momani, Kamal A; Jbarah, Abdel-Aziz Q; Massadeh, Adnan

    2004-10-01

    This article deals with the determination and comparison of heavy metals and water-soluble anions and cations in indoor dust and outdoor dust fall in the petroleum refinery area in Jordan. Three sampling sites were considered in the Jordanian petroleum refinery complex for the collection of dust fall and office dust samples. These samples were analyzed for water-soluble anions (F-, Cl-, Br-, NO3-, C2O4(2-), and SO4(2-)) and cations (Li+, Na+, K+, Mg2+, and Ca2+) using auto-suppressed ion chromatography. Heavy metals (Pb, Cd, Cu, Zn, Cr, Fe, and Al) were determined using flame or graphite-furnace atomic absorption. No correlations were found between heavy metal concentrations in dust fall and office dust samples, indicating different sources. High enrichment factors for heavy metals were found in dust-fall samples, except for Fe and Cr. Zinc showed the highest and cadmium the lowest flux rates.

  10. Nano-metric Dust Particles as a Hardly Detectable Component of the Interplanetary Dust Cloud

    Indian Academy of Sciences (India)

    I. Simonia; Sh. Nabiyev

    2015-09-01

    The present work introduces the hypothesis of existence of a hardly detectable component of the interplanetary dust cloud and demonstrates that such a component is a dust formation consisting of the dust particles of nano-metric dimensions. This work describes the main physical properties of such a kind of nano-dust, and its possible chemical and mineralogical peculiarities proposes new explanations related to reddening of the dynamically cold transneptunian objects on account of scattering their light by nano-dust of the hardly detectable component of the interplanetary dust cloud. We propose the relation for the coefficient of absorption by the nano-dust and provide results of the statistical analysis of the TNO color index–orbital inclinations. We also present a critical assessment of the proposed hypothesis.

  11. Guillain-Barré syndrome: report of two rare clinical cases occurring after allergenic bone grafting in oral maxillofacial surgery

    Science.gov (United States)

    Cicciù, Marco; Herford, Alan Scott; Bramanti, Ennio; Maiorana, Carlo

    2015-01-01

    Guillaine-Barré Syndrome (GBS), also known as post-infectious polyneuropathy or acute idiopathic polyneuritis, is an infrequent disorder of the peripheral nervous system. The cause of GBS is unknown. It has been associated in the past with microbial infections, vaccinations, surgical procedures and debilitation of the patient. The classic signs of GBS occurring in the two patients being reported here are muscle weakness, motor and sensory impairment and ascending paralysis with respiratory involvement. The documented cases involved GBS syndrome following oral and maxillofacial surgery in which allogeneic-banked freeze-dried bone have been utilized along with autogenous grafting. There were no incidents of viral infection, vaccination or the other prodromal incidents involved in these cases. It is believed that the description of these two cases would be of interest in that it may stimulate the reporting of similar anecdotal occurrences by other surgeons. Both patients fully recovered from the GBS and are presently alive and well. PMID:26261679

  12. Cosmic Dust in the 21st Century

    CERN Document Server

    Greenberg, J M; Shen, Chuanjian

    2000-01-01

    The past century of interstellar dust has brought us from first ignoring it to finding that it plays an important role in the evolution of galaxies. Current observational results in our galaxy provide a complex physical and chemical evolutionary picture of interstellar dust starting with the formation of small refractory particles in stellar atmospheres to their modification in diffuse and molecular clouds and ultimately to their contribution to star forming regions. Observations of the properties of dust in very young galaxies will be an important probe of the rates of star formation in terms of the production and destruction of dust grains. Future observations of dust at high spectral and spatial resolution will provide detailed information on processes in collapsing clouds up to star formation. Space missions to comets in the next century will first study them in situ but ultimately will bring back pristine nucleus material which will contain the end product of the collapsing protosolar molecular cloud at ...

  13. Ionization and Dust Charging in Protoplanetary Disks

    CERN Document Server

    Ivlev, A V; Caselli, P

    2016-01-01

    Ionization-recombination balance in dense interstellar and circumstellar environments is a key factor for a variety of important physical processes, such as chemical reactions, dust charging and coagulation, coupling of the gas with magnetic field and the development of magnetorotational instability in protoplanetary disks. We present a self-consistent analytical model which allows us to exactly calculate abundances of charged species in dusty gas, in the regime where the dust-phase recombination dominates over the gas-phase recombination. The model is employed to verify applicability of a conventional approximation of low dust charges in protoplanetary disks, and to discuss the implications for the dust coagulation and the development of the "dead zone" in the disk. Furthermore, the importance of mutually consistent models for the ionization and dust evolution is addressed: These processes are coupled via several mechanisms operating in the disk, and therefore their interplay can be crucial for the ultimate ...

  14. Model of Image Artifacts from Dust Particles

    Science.gov (United States)

    Willson, Reg

    2008-01-01

    A mathematical model of image artifacts produced by dust particles on lenses has been derived. Machine-vision systems often have to work with camera lenses that become dusty during use. Dust particles on the front surface of a lens produce image artifacts that can potentially affect the performance of a machine-vision algorithm. The present model satisfies a need for a means of synthesizing dust image artifacts for testing machine-vision algorithms for robustness (or the lack thereof) in the presence of dust on lenses. A dust particle can absorb light or scatter light out of some pixels, thereby giving rise to a dark dust artifact. It can also scatter light into other pixels, thereby giving rise to a bright dust artifact. For the sake of simplicity, this model deals only with dark dust artifacts. The model effectively represents dark dust artifacts as an attenuation image consisting of an array of diffuse darkened spots centered at image locations corresponding to the locations of dust particles. The dust artifacts are computationally incorporated into a given test image by simply multiplying the brightness value of each pixel by a transmission factor that incorporates the factor of attenuation, by dust particles, of the light incident on that pixel. With respect to computation of the attenuation and transmission factors, the model is based on a first-order geometric (ray)-optics treatment of the shadows cast by dust particles on the image detector. In this model, the light collected by a pixel is deemed to be confined to a pair of cones defined by the location of the pixel s image in object space, the entrance pupil of the lens, and the location of the pixel in the image plane (see Figure 1). For simplicity, it is assumed that the size of a dust particle is somewhat less than the diameter, at the front surface of the lens, of any collection cone containing all or part of that dust particle. Under this assumption, the shape of any individual dust particle artifact

  15. Recycling of steelmaking dusts: The Radust concept

    Directory of Open Access Journals (Sweden)

    Jalkanen H.

    2005-01-01

    Full Text Available Recycling of dusts and other wastes of steelmaking is becoming to a necessity of two reasons: due to high contents of iron oxides dusts are valuable raw material for steelmaking and tightening environmental legislation makes the landfill disposal of wastes more expensive. Fine dust fractions from various stages of steelmaking route contain besides iron and carbon heavy metals especially zinc and lead and heavy hydrocarbons that are acceptable neither for landfill disposal nor for recycling back to processes without any spe4cial treatments. Some theoretical and practical aspects concerning high temperature treatments of steelmaking dusts for removal of hazardous components and production of clean high iron raw material for recycling is discussed in this paper. The Radust technology developed at Koverhar steelwork in Finland for treatment of the most problematic fine fractions of blast furnace and oxygen converter dusts is shortly presented and discussed.

  16. Dust in the 55 Cancri planetary system

    CERN Document Server

    Jayawardhana, R; Greaves, J S; Dent, W R F; Marcy, G W; Hartmann, L W; Fazio, G G; Jayawardhana, Ray; Holland, Wayne S.; Greaves, Jane S.; Dent, William R. F.; Marcy, Geoffrey W.; Hartmann, Lee W.; Fazio, Giovanni G.

    2000-01-01

    The presence of debris disks around $\\sim$ 1-Gyr-old main sequence stars suggests that an appreciable amount of dust may persist even in mature planetary systems. Here we report the detection of dust emission from 55 Cancri, a star with one, or possibly two, planetary companions detected through radial velocity measurements. Our observations at 850$\\mu$m and 450$\\mu$m imply a dust mass of 0.0008-0.005 Earth masses, somewhat higher than that in the the Kuiper Belt of our solar system. The estimated temperature of the dust grains and a simple model fit both indicate a central disk hole of at least 10 AU in radius. Thus, the region where the planets are detected is likely to be significantly depleted of dust. Our results suggest that far-infrared and sub-millimeter observations are powerful tools for probing the outer regions of extrasolar planetary systems.

  17. Models of dust around Europa and Ganymede

    CERN Document Server

    Miljkovic, K; Mason, N J; Zarnecki, J C

    2012-01-01

    We use numerical models, supported by our laboratory data, to predict the dust densities of ejecta outflux at any altitude within the Hill spheres of Europa and Ganymede. The ejecta are created by micrometeoroid bombardment and five different dust populations are investigated as sources of dust around the moons. The impacting dust flux (influx) causes the ejection of a certain amount of surface material (outflux). The outflux populates the space around the moons, where a part of the ejecta escapes and the rest falls back to the surface. These models were validated against existing Galileo DDS (Dust Detector System) data collected during Europa and Ganymede flybys. Uncertainties of the input parameters and their effects on the model outcome are also included. The results of this model are important for future missions to Europa and Ganymede, such as JUICE (JUpiter ICy moon Explorer), recently selected as ESA's next large space mission to be launched in 2022.

  18. [Wood dust as inhalative noxious agent].

    Science.gov (United States)

    Kirsten, D; Liebetrau, G; Meister, W

    1985-01-01

    Wood dust is known as a cause of asthma and chronic bronchitis. From 1979 to 1983 we observed 115 patients with chronic lung diseases, who were exposed to wood dust during many years. We found an irritative pathogenesis in 101 patients with asthma or bronchitis. Twenty nine patients had got a positive skin test, especially with makoré, beech, koto, ash, pine. The inhalation test was positive in 7 of them. The occupational etiology was verified in 5 patients. Besides wood dust itself chemicals for wood protection or wood adhesives can have importance in the pathogenesis of these diseases. Fourteen patients had got alveolitis or lung fibrosis after wood-dust exposition. In each case we found precipitating antibodies against moulds, which could be cultivated from wood dust to which the patients were exposed.

  19. 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.

  20. BONES WITH BIOCERAMICS

    Directory of Open Access Journals (Sweden)

    Wijianto Wijianto

    2017-01-01

    Full Text Available This paper discuss about ceramics in application as bone implant. Bioceramics for instance Hydroxyapatite, usually is abbreviated with HA or HAp, is a mineral that is very good physical properties as bone replacement in human body. To produce Hydroxyapatite, coating process is used which have good potential as they can exploit the biocompatible and bone bonding properties of the ceramic. There are many advantages and disadvantages of bioceramics as bone implant. Advantages of hydroxyapatite as bone implant are rapidly integrated into the human body, and is most interesting property that will bond to bone forming indistinguishable unions. On contrary, disadvantages of hydroxyapatite as bone implant are poor mechanical properties (in particular fatigue properties mean that hydroxyapatite cannot be used in bulk form for load bearing applications such as orthopaedics and poor adhesion between the calcium phosphate coating and the material implant will occur.