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Sample records for teratoma formation posttransplantation

  1. Comparison of Teratoma Formation between Embryonic Stem Cells and Parthenogenetic Embryonic Stem Cells by Molecular Imaging

    Directory of Open Access Journals (Sweden)

    Hongyan Tao

    2018-01-01

    Full Text Available With their properties of self-renewal and differentiation, embryonic stem (ES cells hold great promises for regenerative therapy. However, teratoma formation and ethical concerns of ES cells may restrict their potential clinical applications. Currently, parthenogenetic embryonic stem (pES cells have attracted the interest of researchers for its self-renewing and pluripotent differentiation while eliciting less ethic concerns. In this study, we established a model with ES and pES cells both stably transfected with a double-fusion reporter gene containing renilla luciferase (Rluc and red fluorescent protein (RFP to analyze the mechanisms of teratoma formation. Transgenic Vegfr2-luc mouse, which expresses firefly luciferase (Fluc under the promoter of vascular endothelial growth factor receptor 2 (Vegfr2-luc, was used to trace the growth of new blood vessel recruited by transplanted cells. Bioluminescence imaging (BLI of Rluc/Fluc provides an effective tool in estimating the growth and angiogenesis of teratoma in vivo. We found that the tumorigenesis and angiogenesis capacity of ES cells were higher than those of pES cells, in which VEGF/VEGFR2 signal pathway plays an important role. In conclusion, pES cells have the decreased potential of teratoma formation but meanwhile have similar differentiating capacity compared with ES cells. These data demonstrate that pES cells provide an alternative source for ES cells with the risk reduction of teratoma formation and without ethical controversy.

  2. Teratoma formation of human embryonic stem cells in three-dimensional perfusion culture bioreactors.

    Science.gov (United States)

    Stachelscheid, H; Wulf-Goldenberg, A; Eckert, K; Jensen, J; Edsbagge, J; Björquist, P; Rivero, M; Strehl, R; Jozefczuk, J; Prigione, A; Adjaye, J; Urbaniak, T; Bussmann, P; Zeilinger, K; Gerlach, J C

    2013-09-01

    Teratoma formation in mice is today the most stringent test for pluripotency that is available for human pluripotent cells, as chimera formation and tetraploid complementation cannot be performed with human cells. The teratoma assay could also be applied for assessing the safety of human pluripotent cell-derived cell populations intended for therapeutic applications. In our study we examined the spontaneous differentiation behaviour of human embryonic stem cells (hESCs) in a perfused 3D multi-compartment bioreactor system and compared it with differentiation of hESCs and human induced pluripotent cells (hiPSCs) cultured in vitro as embryoid bodies and in vivo in an experimental mouse model of teratoma formation. Results from biochemical, histological/immunohistological and ultrastuctural analyses revealed that hESCs cultured in bioreactors formed tissue-like structures containing derivatives of all three germ layers. Comparison with embryoid bodies and the teratomas revealed a high degree of similarity of the tissues formed in the bioreactor to these in the teratomas at the histological as well as transcriptional level, as detected by comparative whole-genome RNA expression profiling. The 3D culture system represents a novel in vitro model that permits stable long-term cultivation, spontaneous multi-lineage differentiation and tissue formation of pluripotent cells that is comparable to in vivo differentiation. Such a model is of interest, e.g. for the development of novel cell differentiation strategies. In addition, the 3D in vitro model could be used for teratoma studies and pluripotency assays in a fully defined, controlled environment, alternatively to in vivo mouse models. Copyright © 2012 John Wiley & Sons, Ltd.

  3. Teratoma Formation by Human Embryonic Stem Cells is site-dependent and enhanced by the presence of Matrigel

    DEFF Research Database (Denmark)

    Prokhorova, Tatyana A; Harkness, Linda M; Frandsen, Ulrik

    2008-01-01

    When implanted into immunodeficient mice, human embryonic stem cells (hESC) give rise to teratoma, tumour-like formations containing tissues belonging to all three germ layers. The ability to form teratoma is a sine qua non characteristic of pluripotent stem cells. However, limited data...

  4. Attenuation of teratoma formation by p27 overexpression in induced pluripotent stem cells.

    Science.gov (United States)

    Matsu-ura, Toru; Sasaki, Hiroshi; Okada, Motoi; Mikoshiba, Katsuhiko; Ashraf, Muhammad

    2016-02-15

    Pluripotent stem cells, such as embryonic stem cells or induced pluripotent stem cells, have a great potential for regenerative medicine. Induced pluripotent stem cells, in particular, are suitable for replacement of tissue by autologous transplantation. However, tumorigenicity is a major risk in clinical application of both embryonic stem cells and induced pluripotent stem cells. This study explores the possibility of manipulating the cell cycle for inhibition of tumorigenicity. We genetically modified mouse induced pluripotent stem cells (miPSCs) to overexpress p27 tumor suppressor and examined their proliferation rate, gene expression, cardiac differentiation, tumorigenicity, and therapeutic potential in a mouse model of coronary artery ligation. Overexpression of p27 inhibited cell division of miPSCs, and that inhibition was dependent on the expression level of p27. p27 overexpressing miPSCs had pluripotency characteristics but lost stemness earlier than normal miPSCs during embryoid body and teratoma formation. These cellular characteristics led to none or smaller teratoma when the cells were injected into nude mice. Transplantation of both miPSCs and p27 overexpressing miPSCs into the infarcted mouse heart reduced the infarction size and improved left ventricular function. The overexpression of p27 attenuated tumorigenicity by reducing proliferation and earlier loss of stemness of miPSCs. The overexpression of p27 did not affect pluripotency and differentiation characteristics of miPSC. Therefore, regulation of the proliferation rate of miPSCs offers great therapeutic potential for repair of the injured myocardium.

  5. The postischemic environment differentially impacts teratoma or tumor formation after transplantation of human embryonic stem cell-derived neural progenitors

    DEFF Research Database (Denmark)

    Seminatore, Christine; Polentes, Jerome; Ellman, Ditte

    2010-01-01

    Risk of tumorigenesis is a major obstacle to human embryonic and induced pluripotent stem cell therapy. Likely linked to the stage of differentiation of the cells at the time of implantation, formation of teratoma/tumors can also be influenced by factors released by the host tissue. We have...... analyzed the relative effects of the stage of differentiation and the postischemic environment on the formation of adverse structures by transplanted human embryonic stem cell-derived neural progenitors....

  6. Beta 1 integrin is essential for teratoma growth and angiogenesis

    DEFF Research Database (Denmark)

    Bloch, W; Forsberg, E; Lentini, S

    1997-01-01

    Teratomas are benign tumors that form after ectopic injection of embryonic stem (ES) cells into mice and contain derivatives of all primitive germ layers. To study the role of beta 1 integrin during teratoma formation, we compared teratomas induced by normal and beta1-null ES cells. Injection of ...

  7. Congenital orbital teratoma

    OpenAIRE

    Aiyub, Shereen; Chan, Weng Onn; Szetu, John; Sullivan, Laurence J; Pater, John; Cooper, Peter; Selva, Dinesh

    2013-01-01

    We present a case of mature congenital orbital teratoma managed with lid-sparing exenteration and dermis fat graft. This is a case report on the management of congenital orbital teratoma. A full-term baby was born in Fiji with prolapsed right globe which was surrounded by a nonpulsatile, cystic mass. Clinical and imaging features were consistent with congenital orbital teratoma. Due to limited surgical expertise, the patient was transferred to Adelaide, Australia for further management. The p...

  8. Congenital orbital teratoma.

    Science.gov (United States)

    Aiyub, Shereen; Chan, Wengonn; Szetu, John; Sullivan, Laurence J; Pater, John; Cooper, Peter; Selva, Dinesh

    2013-12-01

    We present a case of mature congenital orbital teratoma managed with lid-sparing exenteration and dermis fat graft. This is a case report on the management of congenital orbital teratoma. A full-term baby was born in Fiji with prolapsed right globe which was surrounded by a nonpulsatile, cystic mass. Clinical and imaging features were consistent with congenital orbital teratoma. Due to limited surgical expertise, the patient was transferred to Adelaide, Australia for further management. The patient underwent a lid-sparing exenteration with frozen section control of the apical margin. A dermis fat graft from the groin was placed beneath the lid skin to provide volume. Histopathology revealed mature tissues from each of the three germ cell layers which confirmed the diagnosis of mature teratoma. We describe the successful use of demis fat graft in socket reconstruction following lid-sparing exenteration for congenital orbital teratoma.

  9. Congenital orbital teratoma

    Directory of Open Access Journals (Sweden)

    Shereen Aiyub

    2013-01-01

    Full Text Available We present a case of mature congenital orbital teratoma managed with lid-sparing exenteration and dermis fat graft. This is a case report on the management of congenital orbital teratoma. A full-term baby was born in Fiji with prolapsed right globe which was surrounded by a nonpulsatile, cystic mass. Clinical and imaging features were consistent with congenital orbital teratoma. Due to limited surgical expertise, the patient was transferred to Adelaide, Australia for further management. The patient underwent a lid-sparing exenteration with frozen section control of the apical margin. A dermis fat graft from the groin was placed beneath the lid skin to provide volume. Histopathology revealed mature tissues from each of the three germ cell layers which confirmed the diagnosis of mature teratoma. We describe the successful use of demis fat graft in socket reconstruction following lid-sparing exenteration for congenital orbital teratoma.

  10. Mature Cystic Renal Teratoma

    International Nuclear Information System (INIS)

    Yavuz, Alpaslan; Ceken, Kagan; Alimoglu, Emel; Akkaya, Bahar

    2014-01-01

    Teratomas are rare germline tumors that originate from one or more embryonic germ cell layers. Teratoma of the kidney is extremely rare, and less than 30 cases of primary intrarenal teratomas have been published to date. We report the main radiologic features of an unusual case of mature cystic teratoma arising from the left kidney in a two-year-old boy. A left-sided abdominal mass was detected on physical examination and B-Mod Ultrasound (US) examination revealed a heterogeneous mass with central cystic component. Computed tomography (CT) demonstrated a lobulated, heterogeneous, hypodense mass extending craniocaudally from the splenic hilum to the level of the left iliac fossa. Nephrectomy was performed and a large, fatty mass arising from the left kidney was excised. The final pathologic diagnosis was confirmed as cystic renal teratoma

  11. Primary medulla oblongata teratomas.

    Science.gov (United States)

    Li, Da; Hao, Shu-Yu; Wu, Zhen; Zhang, Li-Wei; Zhang, Jun-Ting

    2014-09-01

    Medulla oblongata teratomas are rare. The authors report 2 new cases of teratomas that occurred exclusively in the medulla oblongata. The first case was in a 9-year-old boy who presented with a 6-month history of neck pain and repeated paroxysmal vomiting. Based on preoperative radiographic findings, the initial diagnosis was of an intraaxial medulla oblongata hemangioblastoma. Intraoperatively, the cystic component of the tumor was gray, gelatinous, and soft in consistency. The solid component was light pink, rubbery, and nodular in appearance, with an identifiable boundary. The lesion was completely removed. Histopathological investigation revealed a mature teratoma. Postoperatively, the patient was supported with ventilator assistance and received a tracheotomy, but died of intracranial infection. The second case was in a 10-year-old boy with intermittent headache for 1 month. Radiographs revealed an exophytic cystic and solid lesion with dorsal involvement of the medulla oblongata. The lesion was predominantly solid, pinkish gray, tenacious, and moderately vascularized, with clearly delineated surgical dissection planes. The histopathological examination confirmed a diagnosis of immature teratoma. Total resection was achieved, followed by postoperative chemotherapy. He was alive without recurrence of the lesion or symptoms at 59 months after surgery. Resection of medulla oblongata teratoma is challenging, with inherent surgical risks that are contingent on the tumor growth pattern. Teratomas should be considered in the differential diagnosis of brainstem lesions. Chemotherapy has been suggested for immature teratomas. Long-term follow-up and larger studies of teratomas in unusual locations are required to improve practitioners' understanding of this disease's treatment and outcomes.

  12. Fetus in Jetu and Teratoma

    African Journals Online (AJOL)

    Department of Radiology, University of Natal, and Depart- ment of Paediatrics and ... imperfect X-ray films). Since the 1I ... tained a teratoma, with 5 fetiform structures. The latter ... dental rudiments of the fetus have suffered some un- paralleled ...

  13. Posttransplantation lymphoproliferative disease involving the pituitary gland.

    Science.gov (United States)

    Meriden, Zina; Bullock, Grant C; Bagg, Adam; Bonatti, Hugo; Cousar, John B; Lopes, M Beatriz; Robbins, Mark K; Cathro, Helen P

    2010-11-01

    Posttransplantation lymphoproliferative disorders (PTLD) are heterogeneous lesions with variable morphology, immunophenotype, and molecular characteristics. Multiple distinct primary lesions can occur in PTLD, rarely with both B-cell and T-cell characteristics. Lesions can involve both grafted organs and other sites; however, PTLD involving the pituitary gland has not been previously reported. We describe a patient who developed Epstein-Barr virus-negative PTLD 13 years posttransplantation involving the terminal ileum and pituitary, which was simultaneously involved by a pituitary adenoma. Immunohistochemistry of the pituitary lesion showed expression of CD79a, CD3, and CD7 with clonal rearrangements of both T-cell receptor gamma chain (TRG@) and immunoglobulin heavy chain (IGH@) genes. The terminal ileal lesion was immunophenotypically and molecularly distinct. This is the first report of pituitary PTLD and illustrates the potentially complex nature of PTLD. Copyright © 2010 Elsevier Inc. All rights reserved.

  14. Post-transplantation diabetes mellitus: an overview

    Directory of Open Access Journals (Sweden)

    Igor Aleksandrovich Sklyanik

    2015-04-01

    Full Text Available This review presents an analysis of clinical and experimental studies related to post-transplantation diabetes mellitus (PTDM – a specific complication after solid organ transplantation.A search of the databases eLibrary, PubMed and Scopus using the keywords «posttransplantation diabetes mellitus», «new onset diabetes after transplantation», «transplantation» and «immunosuppression» yielded in 523 results, including four from Russian literature (one original research manuscript. The analysis included original research, reviews, meta-analyses and monographs published not before 2005 in Russian and English. A total of 60 relevant original researches and reviews were included in this review.Diagnostic criteria, disease risk factors and potential pathogenic mechanisms were all considered. The mechanisms of the diabetogenic effect of modern immunosuppressive drugs were analysed. The principles of pre- and post-transplantation screening for PTDM and optimal management strategies for patients with PTDM are presented. The current controversial issues concerning the various aspects of PTDM are discussed.

  15. A case of intracranial teratoma

    International Nuclear Information System (INIS)

    Shiota, Madoka; Ando, Yukinori; Takashima, Sachio; Hori, Tomokatsu; Hiramoto, Shinsuke.

    1985-01-01

    A case of neonatal intracranial teratoma was examined on ultrasonography (US), computed tomography (CT) and tumor markers in serum, CSF and tumor tissue. This 27-day-old male infant was pointed out a head enlargement by prenatal sonography at 39 weeks' gestation. He admitted to our hospital at the age of one day after cesarean section. His birth weight was 4430 g and head circumstance 47.5 cm. On admission, physical and neurological examinations reveled big head, weak crying, twiching and sun set phenomenon. The optic fundi were normal. The CT scan at 1 day demonstrated the marked enlargement of lateral ventricles and the supratentorial large polycystic mass with calcifications at midline area. Transfontanelle sonography also delineated the polycystic mass and enlarged ventricle. Ventricular tap showed bloody CSF. Alpha-Fetoprotein and carcinoembryonic antigen level in CSF was higher than those in serum. Postmortam tumor necropsy revealed a teratoma including mature squamous epithelium, muscle, cartilage, bone, lymphoid and nervous tissue. There were immature mesenchymal cells in some parts. The immune histochemical method showed positive staining to AFP in intestinal and respiratory epithelium, and to CEA in intestinal epithelium and immature mesenchymal cells. In summary, these characteristic findings of US, CT and tumor marker in CSF have a diagnostic value of intracranial teratoma. (author)

  16. Ultrasonographic Findings of Fetal Congenital Intracranial Teratoma

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    Lee, Hak Jong [Seoul National University College of Medicine, Seoul (Korea, Republic of); Lee, Young Ho; Song, Mi Jin; Cho, Jeong Yeon; Min, Jee Yeon; Moon, Min Hwan; Kim, Jeong Ah [Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2005-06-15

    To evaluate the sonographic findings of fetal congenital intracranial teratoma. From 1994 to 2002, of the 11 fetuses which had been diagnosed with fetal intracranial tumors after second level fetal ultrasonography, the six that were confirmed after autopsy as congenital intracranial teratomas were included in our study. The sonographic findings, including size, homogeneity, echogenicity compared with surrounding normal brain tissues, cystic components, and tumor related calcification, were retrospectively evaluated. The incidence of fetal congenital intracranial teratoma out of all fetal intracranial tumors was 54.5% (6 of 11 cases) during the 8-year period. The mean mass size was 7.4 cm (3.0-15.0 cm). Two thirds of (4/6) of the teratoma cases showed high echogenicity compared with normal brain tissues, and two thirds (4/6) showed heterogeneous echogenicity. Four teratoma cases (67%) showed cysts in the mass with a mean size of 1.9cm. One third (2/6) showed calcifications within the tumor. Out of the six cases, two had oropharyngeal teratoma with extension into the intracranial portion (so called epignathus) and showed homogenous mass without any cysts or calcifications. The typical sonographic appearance of intracranial teratoma was a heterogeneous, hyperechoic mass with cysts. In the epignathus cases, the sonographic appearances differed somewhat from the others. An understanding of the sonographic findings of fetal intracranial teratoma will help in the timely counseling of the parents and in obstetric decision making

  17. Immature ovarian teratoma in a postmenopausal woman

    DEFF Research Database (Denmark)

    Ornvold, K; Detlefsen, G U; Horn, T

    1987-01-01

    We report the first case of immature ovarian teratoma occurring after menopause in a 57-year-old, 3 years postmenopausal woman. Within one year after resection of the teratoma she developed peritoneal botryoid rhabdomyosarcoma, which probably originated from initially unrecognized rhabdomyoblasts...

  18. Brief Report: External Beam Radiation Therapy for the Treatment of Human Pluripotent Stem Cell-Derived Teratomas.

    Science.gov (United States)

    Lee, Andrew S; Tang, Chad; Hong, Wan Xing; Park, Sujin; Bazalova-Carter, Magdalena; Nelson, Geoff; Sanchez-Freire, Veronica; Bakerman, Isaac; Zhang, Wendy; Neofytou, Evgenios; Connolly, Andrew J; Chan, Charles K; Graves, Edward E; Weissman, Irving L; Nguyen, Patricia K; Wu, Joseph C

    2017-08-01

    Human pluripotent stem cells, including human embryonic stem cells (hESCs) and human induced PSCs (hiPSCs), have great potential as an unlimited donor source for cell-based therapeutics. The risk of teratoma formation from residual undifferentiated cells, however, remains a critical barrier to the clinical application of these cells. Herein, we describe external beam radiation therapy (EBRT) as an attractive option for the treatment of this iatrogenic growth. We present evidence that EBRT is effective in arresting growth of hESC-derived teratomas in vivo at day 28 post-implantation by using a microCT irradiator capable of targeted treatment in small animals. Within several days of irradiation, teratomas derived from injection of undifferentiated hESCs and hiPSCs demonstrated complete growth arrest lasting several months. In addition, EBRT reduced reseeding potential of teratoma cells during serial transplantation experiments, requiring irradiated teratomas to be seeded at 1 × 10 3 higher doses to form new teratomas. We demonstrate that irradiation induces teratoma cell apoptosis, senescence, and growth arrest, similar to established radiobiology mechanisms. Taken together, these results provide proof of concept for the use of EBRT in the treatment of existing teratomas and highlight a strategy to increase the safety of stem cell-based therapies. Stem Cells 2017;35:1994-2000. © 2017 AlphaMed Press.

  19. A rare case of benign omentum teratoma

    Directory of Open Access Journals (Sweden)

    Sforza Marcos

    2012-01-01

    Full Text Available Introduction. Mature teratomas (benign cystic teratomas or dermoid cysts are among the most common ovarian tumours; however, teratomas of the omentum and mesentery are extremely rare. Teratoma in the intraperitoneal cavity is uncommon and atypical, and it is even more uncommon in adulthood. Case Outline. An 82-year-old female was admitted to our department with clinical signs of abdominal tumour. The ultrasound scan and preoperative laboratory tests were done. Explorative laparotomy revealed tumour with torsion on its pedicle at the greater omentum. After removal of the mass and the incision a tooth and hair were found, characteristics of teratoma. Conclusion. The excision was very effective and also definitive treatment for this case. The patient recovered well and was discharged 3 days later. The patient probably carried the tumour all her life asymptomatically until admission.

  20. Malignant orbital teratoma in a neonate: A clinicopathological case report

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    M VS Prakash

    2017-01-01

    Full Text Available Teratoma of the orbit is rare; very few cases have been published in literature. A case of orbital teratoma in a neonate is presented where the proptosis was massive enough to obscure the eyeball. Clinically, the diagnosis of teratoma was considered. As there was no possibility of salvaging the eye, exenteration of the orbit was done. Orbital teratomas are generally benign. Histopathological examination revealed the features of malignant teratoma.

  1. Computed tomography of the mediastinal teratoma

    International Nuclear Information System (INIS)

    Byun, Hong Sik; Im, Jung Gi; Han, Man Chung

    1984-01-01

    Computed tomographic findings in fifteen cases of anterior mediastinal teratoma are presented and compared with radiographic, and pathologic findings. Specific CT characteristics of anterior mediastinal teratoma are predominantly fatty mass with a denser dependent element and globular calcification in a solid protuberance into the cystic cavity. Six cases presented above described characteristic CT findings. Four cases presented water density mass with surrounding thick wall. Fat and calcific densities were present in nine and seven respectively, so these findings are frequently absent. Thick wall was present in all cases. So thick walled cyst even in the absence of fatty or calcific densities is highly suggestive of anterior mediastinal teratoma

  2. Bipartite Anterior Extraperitoneal Teratoma: Evidence for the Embryological Origins of Teratomas?

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    D. J. B. Keene

    2011-01-01

    Full Text Available Teratomas are thought to arise from totipotent primordial germ cells (PGCs Dehner (1983 which may miss their target destination Moore and Persaud (1984. Teratomas can occur anywhere from the brain to the coccygeal area but are usually in the midline close to the embryological position of the gonadal ridges Bale (1984, Nguyen and Laberge (2000. We report a case of a bipartite anterior extraperitoneal teratoma. This is an unusual position for a teratoma, but one which may support the “missed target” theory of embryology.

  3. Gigantic teratoma - retroperitoneal tumor: a case report

    International Nuclear Information System (INIS)

    Figueiredo, Rossana Lopes de; Nobrega, Rosangela Figueiredo; Toscano, Carlos Alberto Regis

    1996-01-01

    The authors report a case of primary retroperitoneal teratoma which has grown for seven years. the diagnosis was presumed through image diagnostic methods and it was confirmed after surgery and histopathology analysis. (author). 7 refs., 6 figs

  4. NEONATAL TERATOMA PRESENTING AS HYGROMA-COLLI

    NARCIS (Netherlands)

    JAARSMA, AS; TAMMINGA, RYJ; DELANGEN, ZJ; NIKKELS, PGJ; KIMPEN, JLL

    We describe a neonate with a large tumour involving cranial, cervical and upper mediastinal regions, which presented clinically as hygroma colli. Radiological and pathological investigations showed characteristics of a mature teratoma and prominent cystic components within the tumour. These findings

  5. Mature teratoma of the posterior mediastinum

    Energy Technology Data Exchange (ETDEWEB)

    Kurosaki, Y.; Tanaka, Y.O.; Itai, Y. [Department of Radiology, Institute of Clinical Medicine, University of Tsukuba, Tsukuba-shi, Ibaraki-ken 305 (Japan)

    1998-02-01

    The vast majority of germ cell tumors in the thorax arise at or near the thymus. We report a case of a 41-year-old man with mature teratoma of the posterior mediastinum. He was asymptomatic and was incidentally found to have a posterior mediastinal mass. Computed tomography was helpful in suggesting a diagnosis of mature teratoma by demonstrating the presence of fat and calcification. The differential diagnosis included neurogenic tumors, liposarcoma, and extramedullary hematopoiesis. (orig.) With 2 figs., 18 refs.

  6. Mature teratoma of the posterior mediastinum

    International Nuclear Information System (INIS)

    Kurosaki, Y.; Tanaka, Y.O.; Itai, Y.

    1998-01-01

    The vast majority of germ cell tumors in the thorax arise at or near the thymus. We report a case of a 41-year-old man with mature teratoma of the posterior mediastinum. He was asymptomatic and was incidentally found to have a posterior mediastinal mass. Computed tomography was helpful in suggesting a diagnosis of mature teratoma by demonstrating the presence of fat and calcification. The differential diagnosis included neurogenic tumors, liposarcoma, and extramedullary hematopoiesis. (orig.)

  7. Posterior mediastinal teratoma diagnosis by computerized tomography and ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Choo, Yeon Myung; Im, Chung Kie; Yeon, Kyung Mo; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1984-09-15

    Teratomas, usually arising in the anterior mediastinum, are very uncommon in the posterior mediastinum. Embryologic development of anterior mediastinal teratoma is thought to be from thymic anlage which descends from the third bronchial cleft and pouch, while that of posterior mediastinal teratoma is thought to be from the remnant of notochord. CT findings of posterior mediastinal teratomas are not different from teratomas elsewhere, containing fat, calcification, soft tissue and thick walled cyst. Ultrasonographic findings are mixed echogenic mass containing cystic portion, highly reflective solid portion and area of acoustic shadowing. Authors recently experienced 2 cases of surgically proven posterior mediastinal teratoma and report with review of literature.

  8. Posterior mediastinal teratoma diagnosis by computerized tomography and ultrasonography

    International Nuclear Information System (INIS)

    Choo, Yeon Myung; Im, Chung Kie; Yeon, Kyung Mo; Han, Man Chung

    1984-01-01

    Teratomas, usually arising in the anterior mediastinum, are very uncommon in the posterior mediastinum. Embryologic development of anterior mediastinal teratoma is thought to be from thymic anlage which descends from the third bronchial cleft and pouch, while that of posterior mediastinal teratoma is thought to be from the remnant of notochord. CT findings of posterior mediastinal teratomas are not different from teratomas elsewhere, containing fat, calcification, soft tissue and thick walled cyst. Ultrasonographic findings are mixed echogenic mass containing cystic portion, highly reflective solid portion and area of acoustic shadowing. Authors recently experienced 2 cases of surgically proven posterior mediastinal teratoma and report with review of literature.

  9. A Rare Case of Immature Ovarian Teratoma with Gliomatosis Peritonei

    African Journals Online (AJOL)

    KEY WORDS: Glial tissue, gliomatosis peritonei, immature teratoma, India, ovary. Case Report .... astrocytes in the fetal nerve tissue. GFAP immunostain confirms ... Immature teratoma of the ovary: A clinicopathology study of 28 cases. Indian.

  10. Cleft palate caused by congenital teratoma.

    Science.gov (United States)

    Veyssière, Alexis; Streit, Libor; Traoré, Hamady; Bénateau, Hervé

    2017-02-01

    A cleft palate results from incomplete fusion of the lateral palatine processes, the median nasal septum and the median palatine process. This case report describes a rare case of congenital teratoma originating from the nasal septum that may have interfered with the fusion of the palatal shelves during embryonic development, resulting in a cleft palate. An infant girl was born at 40 weeks of gestation weighing 3020 g with a complete cleft palate associated with a large central nasopharyngeal tumour. Computed tomography (CT) of the head showed a well defined mass of mixed density. The tumour was attached to the nasal septum in direct contact with the cleft palate. A biopsy confirmed the teratoma. Tumour resection was performed at 5 months, soft palate reconstruction at 7 months and hard palate closure at 14 months. There was no sign of local recurrence 1 year later. Most teratomas are benign and the prognosis is usually good. However, recurrence is not rare if germ cell carcinomatous foci are present within the teratoma. For these reasons, we advocate the use of a two-stage procedure in which closure of the cleft palate is postponed until histological examination confirms complete excision of the teratoma.

  11. Mediastinal Mature Teratoma Revealed by Empyema

    Directory of Open Access Journals (Sweden)

    Mohammed Raoufi

    2016-01-01

    Full Text Available Teratomas are germ cell tumors, manifested with a great variety of clinical features; the most common extragonadal site is the anterior mediastinum. In this case, we report the patient with a large mature mediastinal teratoma with several components of ectodermal and endothermal epithelium. A 24-year-old female patient presented with history of persistent chest pain and progressively aggravating dyspnea for the previous 3 months. A chest X-ray showed a large opacity of the entire left hemithorax. Transcutaneous needle aspiration revealed a purulent fluid. The tube thoracostomy was introduced and the effusion was evacuated. Some weeks later, patient was seen in emergency for persistent cough and lateral chest pain. CT scan revealed a mass of the left hemithorax. The mass showed heterogeneous density, without compressing mediastinum great vessels and left hilar structures. Lipase value was elevated in needle aspiration. The patient underwent a total resection of the mediastinum mass via a left posterolateral thoracotomy. Microscopy revealed a mature teratoma with cystic structures. The patient subsequently made a full recovery. This case provide benign mediastinal teratoma with total atelectasis of left lung and elevated lipase value in needle transcutaneous aspiration; this event is explained by pancreatic component in the cystic tumor. Total removal of the tumor is adequate treatment for this type of teratoma and the prognosis is excellent.

  12. Teratoma congênito de orofaringe: relato de caso Oropharyngeal congenital teratoma: a case report

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    Yuri Seguchi Chaves

    2005-02-01

    Full Text Available O teratoma congênito de orofaringe é o tipo mais raro de teratoma, compreendendo apenas 2% desses tumores fetais. O diagnóstico deve ser realizado o mais precocemente possível, preferencialmente durante o pré-natal. O prognóstico irá depender do tamanho e localização da lesão, da velocidade de crescimento desta, do envolvimento de estruturas intracranianas e da ressecção adequada do tumor com equipe multidisciplinar. Relatamos o caso de uma paciente que teve diagnosticado durante a gestação feto com teratoma congênito de orofaringe (epignathus por meio de ultra-sonografia. O feto evoluiu para óbito intra-uterino na 29ª semana de gestação, sendo então induzido o parto por via vaginal. O exame anatomopatológico revelou feto do sexo feminino, compatível com 27-28 semanas, teratoma orofaríngeo e outras malformações congênitas.Oropharyngeal teratoma is the most rare type of teratoma, with only 2% of fetal teratomas. The diagnosis must be established as early as possible, preferably during the prenatal period. The prognosis will depend on the size and location of the lesion, growth rate of the lesion, degree of intracranial spread, its resectability, and immediate care at birth by a multisciplinary team. We report aparticular case of congenital oropharyngeal teratoma (epignathus. The diagnosis was made during the prenatal period by ultrasound, and the fetus evolved to intrauterine death at the 29th week. The anatomopathological examination revealed a female fetus, compatible with 27-28 weeks, oropharyngeal teratoma and congenital malformations.

  13. Post-transplantation Infections in Bolivia.

    Science.gov (United States)

    Arze, S; Arze, L; Abecia, C

    2016-03-01

    Over 26 years, we found 46 infectious episodes in 350 kidney transplant recipients. Fifteen were urinary tract infections, recurrent in 4 patients. There were 8 cytomegalovirus infections, three of them fatal when intravenous (IV) ganciclovir was not available. Seven patients had a reactivation of tuberculosis (TB) in the pleura, cervical spine, lumbar spine, knee, ankle, skin and peritoneum, respectively, and were all resolved satisfactorily with conventional anti-TB therapy. Three patients transplanted before routine prophylaxis with the use of acyclovir developed an extensive herpes zoster infection in the 1st 6 months after transplantation, which was resolved with the use of oral acyclovir, and 1 had a disseminated herpes simplex infection resolved with the use of IV acyclovir. Three patients transplanted before routine prophylaxis with trimethoprim sulfa developed Pneumocystis carinii pneumonia in the 1st 6 months after transplantation, which was fatal in one of them. In 2 patients, we found a Nocardia infection, confined to the lung, which was cured in one of the cases and systemic and fatal in the other. Two patients transplanted before routine prophylaxis with the use of nystatin developed esophageal candidiasis in the 1st 6 months after transplantation. One patient developed infective endocarditis in a stenotic bicuspid aortic valve and died 10 years later after another incident of infective endocarditis at the prosthetic aortic valve. Two patients developed an extensive condyloma at the penis, perianal region, and perineum owing to human papillomavirus, requiring extensive surgical resection and podophyllin applications. Another patient developed fatal post-transplantation lymphoproliferative disease due to Epstein-Barr virus infection 15 years after transplantation. One patient developed a severe and fatal mucocutaneous leishmaniasis with no response to conventional antimonial therapy. It is interesting to note that despite Chagas disease being endemic

  14. Teratoma of the posterior fossa CT and MR aspects A case

    International Nuclear Information System (INIS)

    Pina, J.I.; Feijoo, R.; Lasierra, R.; Medrano, J.; Benito, J.L. de

    1994-01-01

    The CT and MR findings are reported for a patient diagnosed as having teratoma of the posterior fossa with onset in the form of intracranial hypertension. The objective of this article is to report the detection of the lesion, as well as its origin in the closure defect of the cranial cavity with the formation of a cutaneous fistula, and review the recent literature

  15. Gigantic teratoma - retroperitoneal tumor: a case report; Teratoma gigante - tumor retroperitoneal: relato de um caso

    Energy Technology Data Exchange (ETDEWEB)

    Figueiredo, Rossana Lopes de [Paraiba Univ., Campina Grande, PB (Brazil). Faculdade de Medicina; Franca Costa, Hamilton Belo de [Hospital Geral de Campina Grande, PB (Brazil); [Clinica Pronto-Socorro Infantil, Campina Grande, PB (Brazil); Nobrega, Rosangela Figueiredo [Clinica Inside, Campina Grande, PB (Brazil); Toscano, Carlos Alberto Regis [Hospital Pedro I, Campina Grande, PB (Brazil)

    1996-03-01

    The authors report a case of primary retroperitoneal teratoma which has grown for seven years. the diagnosis was presumed through image diagnostic methods and it was confirmed after surgery and histopathology analysis. (author). 7 refs., 6 figs.

  16. Rare primary retroperitoneal teratoma masquerading as adrenal ...

    African Journals Online (AJOL)

    J.M. Ratkal

    Abstract. Objectives: To present a rare case of Primary mature cystic teratoma of right adrenal gland in adult female with an aim to review the published literature. Materials and Methods: The case details of a lady presenting with vague upper abdominal pain and on investigation was found to have a right adrenal mass were ...

  17. Mature cystic teratomas: Relationship between histopathological ...

    African Journals Online (AJOL)

    ... tumor size, symptoms related to MCT and laterality of the tumor did not differ among the patients according to the MCT contents. Conclusions: Our findings suggest no relationship between the clinical features and histopathological contents of MCTs. Key words: Histopathological contents, mature cystic teratoma, ovarian, ...

  18. Magnetic Resonance Imaging Verification of a Case of Sacrococcygeal Teratoma

    OpenAIRE

    Dedushi, Kreshnike; Kabashi, Serbeze; Mucaj, Sefedin; Ramadani, Naser; Hoxhaj, Astrit; Shatri, Jeton; Hasbahta, Gazmend

    2016-01-01

    Although rare, sacrococcygeal teratoma is the most common congenital neoplasm, occurring in 1 in 40,000 infants. Approximately 75% of affected infants are female. The aim of the present study was to correlate ultrasonography and magnetic resonance imaging (MRI) findings in patients with fetal sacrococcygeal teratoma. Three pregnant women in 27th week of gestation underwent fetal MRI after ultrasonography examination, with findings suggestive for fetal sacrococcygeal teratoma. Tumor size, loca...

  19. Teratoma with intraventricular free fat on CT

    International Nuclear Information System (INIS)

    Miura, Naohisa; Fuchinoe, Tokuro; Yahagi, Yasuji; Nakamura, Toshihiko

    1983-01-01

    Intracranial fat-containing congenital tumors are characterized by negative absorption values on computed tomography(CT). We are reporting a case of teratoma with intraventricular free fat diagnosed preoperatively by CT. The case is a 19-year-old female who was admitted to our hospital because of contineous severe headache, nausea and vomiting. At the time of admission, her physical and neurological examination was negative except for bilateral papilledema. CT demonstrated marked enlargement of the right lateral ventricle. In addition, there was negative absorption value (-90 H.U.), suggesting free fat, within right frontal horn layering above the CSF with a fluid level. Metrizamide ventriculography demonstrated complete obstruction and revealed an irregular shadow defect at the right foramen of Monro. At surgery, yellowish cheese-like material, white hair was found on the surface of the CSF. Tumor arose from the floor of the right foramen of Monro and extended upward. The patient made an uneventful recovery and was discharged 17 days after surgery. Intraventricular free fat is likely that to be released from the teratoma cyst ruptured spontaneously when the patient complained of severe headache 40 days prior to admission. There have been several published reports of the CT appearances of intracranial fat-containing tumors, however, teratoma with intraventricular free fat is very rare. It was concluded that fat-containing tumors should be highly suspected, when negative absorption values were found on CT. (author)

  20. Teratoma Sacrococcigeo Neonatal, reporte de un caso de autopsia Neonatal Sacrococcygeal Teratomas, autopsy case report

    Directory of Open Access Journals (Sweden)

    Julio Cesar Mantilla

    2010-08-01

    Full Text Available Introducción: Los teratomas sacrococcígeos, constituyen una neoplasia que pese a su baja frecuencia, es una de las más comunes en neonatos. Se describe un caso de un feto muerto con hallazgos histopatológicos de un teratoma sacro coccígeo inmaduro.Pacientes y Métodos: Mujer de 26 años de edad en su cuarto embarazo de 32 semanas de gestación, quien presenta amenaza de parto pre término. Se le realiza una ecografía obstétrica que informa la presencia de una masa sacra fetal, e hidrops fetal. Se realizó cesárea y se obtiene un óbito fetal de sexo femenino. El estudio anatomopatológico evidenció un teratoma sacrococcígeo inmaduro. Conclusiones: En los teratomas sacrococcígeos fetales, el desarrollo de hidrops fetal, insuficiencia cardiaca y gran tamaño tumoral son indicadores de mal pronóstico. El diagnóstico prenatal, la planificación del parto, la estabilización perinatal y la resección quirúrgica del tumor, pueden hacer posible la sobre vida en estos pacientes. Salud UIS 2010; 42: 127-131Introduction: Sacrococcygeal teratomas are neoplasm that despite their low frequency, are one of the most common in newborns. We describe a case of a dead fetus with an immature sacrococcygeal teratoma, its radiological and histological findings. Patients and Methods: A 26 years old woman in the fourth pregnancy of 32 weeks' of gestation, who presented the threat of pre-term birth. We performed obstetric ultrasound reporting the presence of a fetal sacral mass and fetal hydrops. Caesarean section was run and got a female fetal death. Pathologic study showed immature sacrococcygeal teratoma. Conclusions: In fetal sacrococcygeal teratomas, the development of fetal hydrops, heart failure and large tumor size are indicators of poor prognosis. Prenatal diagnosis, planning delivery, the postnatal stabilization period and surgical resection of the tumor, can make survival possible in these patients. Salud UIS 2010; 42: 127-131.

  1. Ovarian cystic teratoma containing balls of fat. A case report

    International Nuclear Information System (INIS)

    Salinas, A.; Rebolledo, M.; Escribano, M.; Alejo, J. P.; Morenom, J.

    1998-01-01

    We present the case of a ovarian cystic teratoma characterized predominantly by the mobile balls floating in the intra cystic fluid. Ultrasonography demonstrated their marked echo reflectivity and computed tomography revealed that they had the density of fat. We establish a relationship among the ultrasound, computed tomography and histological findings in this uncommon type of ovarian cystic teratoma. (Author) 6 refs

  2. Congenital orbital teratoma | Onyekwe | Nigerian Journal of Clinical ...

    African Journals Online (AJOL)

    This is a case report of a baby with a protruding orbital mass in the left eye with all classical clinical features of teratoma. Though the histopathological report fell short of confirming the diagnosis the clinical features and outcome of management strongly suggest that the lesion is a teratoma. Multidisciplinary approach to the ...

  3. Managing Sacrococcygeal Teratoma in a New Born of a ...

    African Journals Online (AJOL)

    Managing Sacrococcygeal Teratoma in a New Born of a Psychopathic Widow: Case Report. CEO Onuoha, CC Amah, HA Ezike. Abstract. Background: Sacrococcygeal tumors are composite embryonal tumours reflecting any one or more of embryonal/foetal remnants such as germinoma, embryonal carcinoma, teratoma, ...

  4. The Impact of Liver Graft Injury on Cancer Recurrence Posttransplantation.

    Science.gov (United States)

    Li, Chang-Xian; Man, Kwan; Lo, Chung-Mau

    2017-11-01

    Liver transplantation is the most effective treatment for selected patients with hepatocellular carcinoma. However, cancer recurrence, posttransplantation, remains to be the critical issue that affects the long-term outcome of hepatocellular carcinoma recipients. In addition to tumor biology itself, increasing evidence demonstrates that acute-phase liver graft injury is a result of hepatic ischemia reperfusion injury (which is an inevitable consequence during liver transplantation) and may promote cancer recurrence at late phase posttransplantation. The liver grafts from living donors, donors after cardiac death, and steatotic donors have been considered as promising sources of organs for liver transplantation and are associated with high incidence of liver graft injury. The acute-phase liver graft injury will trigger a series of inflammatory cascades, which may not only activate the cell signaling pathways regulating the tumor cell invasion and migration but also mobilize the circulating progenitor and immune cells to facilitate tumor recurrence and metastasis. The injured liver graft may also provide the favorable microenvironment for tumor cell growth, migration, and invasion through the disturbance of microcirculatory barrier function, induction of hypoxia and angiogenesis. This review aims to summarize the latest findings about the role and mechanisms of liver graft injury resulted from hepatic ischemia reperfusion injury on tumor recurrence posttransplantation, both in clinical and animal cohorts.

  5. Extramedullary spinal teratoma presenting with recurrent aseptic meningitis.

    Science.gov (United States)

    Mpayo, Lucy L; Liu, Xiao-Hong; Xu, Man; Wang, Kai; Wang, Jiao; Yang, Li

    2014-06-01

    Spinal teratomas are extremely rare; they constitute meningitis. A 7-year-old boy presented with paroxysmal abdominal pain and a history of recurrent aseptic meningitis. Kernig and Brudzinski signs were present. Lumber puncture revealed pleocytosis with no evidence of bacteria growth. Imaging of the spine revealed a cystic lesion in spinal cord at thoracic level 9-11. Endoscopic excision of the cyst was successfully performed. Surgical and histopathological findings confirmed extramedullary matured teratoma. As the symptomatic attacks of spontaneous rupture of spinal teratoma resemble presentations of Mollaret meningitis, spinal teratoma should be considered in the differential diagnosis of Mollaret meningitis. We describe a rare example of spinal teratoma causing recurrent meningitis. Spine imaging should be considered in individuals with recurrent aseptic meningitis as this promotes earlier diagnosis, more appropriate treatment, and improved neurological outcome. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Teratoma do ovario com estruturas semelhando cristalino

    Directory of Open Access Journals (Sweden)

    C. Magarinos Torres

    1940-01-01

    Full Text Available Em uma mulher, brasileira, de côr parda, com 48 anos de idade, morta com tuberculose do peritoneo, tuberculose peribronquica do lóbo superior do pulmão esquerdo e tuberculose cronica fibrosa do apice de ambos os pulmões, a necropsía revelou a existencia de um teratoma no ovario esquerdo. O ovario, pouco aumentado de volume, é constituído por duas porções de tamanho sensivelmente egual, de consistencia firme, separadas, em sua superficie, por profundo sulco. Ao córte, tem a aparencia de tecido fibroso em cuja espessura existem numerosos pequenos cistos. Ao microscopio, os cistos são revestidos por epitelio descontinuo, despertando grande interesse o seu conteúdo. Este é formado por fibras e células com morfologia semelhante ás do cristalino. Sugerimos a possibilidade de que, no presente teratoma (Teratoma lentifer, de lens, lentis: cristalino, e ferre: produzir haja participado, de modo dominante, o ectodérme, e mesmo uma região circumscrita do ectodérme, a qual corresponderia aquela emque se desenvolve, habitualmente, a placa do cristalino (« Linsenplatte ». A multiplicidade e a presença exclusiva de estruturas figurando saculos cristalinicos (« Linsensäckchen » são argumentos a favor de uma origem de ponto restrito do ectodérme, destinado a desenvolvimento posterior especifico, qual o da formação do cristalino.

  7. Ultrasonographic Findings of Prepubertal Testicular Teratoma

    International Nuclear Information System (INIS)

    Won, Jang Han; Cho, Jae Ho

    2005-01-01

    To evaluate the ultrasonographic findings of testicular teratoma arising in pre-pubertal children. We studied 6 cases in 5 patients with pathologically proven testicular teratoma. Ultrasonography was performed in all cases and MRI in 5 cases. The location, size, shape, margin and internal echo pattern of the lesion were evaluated on ultrasonography and the shape, signal intensity and presence or absence of contrast enhancement were evaluated on MRI. The shape of all cases was round or oval and the lesion size ranged from 0.5 to 3.5 cm (average, 1.7 cm). Four of 6 cases were seen as cystic lesions, Three of which were multilocular and one was unilocular. The cystic lesions were filled with echo-free fluid without any solid component. The inner wall and septa were minutely granulated. One of 6 cases was seen as a predominantly cystic lesion containing heterogeneous, high echoic portions. One case was seen as a heterogeneous mixed echoic lesion with dirty posterior sonic shadowing. Three of the 4 cases seen as a cyst on ultrasonography were also seen as a cyst on MRI. In one case seen as a predominantly cystic lesion on ultrasonography, the periphery of the lesion was hypointense and the center was hyperintense on T2-weighted image. The remaining case seen as a heterogeneous mixed echoic mass was markedly heterogeneous in signal intensity both on T2- and T1-weighted images and hyperintense fat components were noted. Contrast enhancement was not seen in any of the 4 cases. On ultrasonography, pre-pubertal testicular teratoma is commonly seen as a multilocular or unilocular cyst and a minutely granulated appearance is noted in the inner wall or septa of the cystic lesion

  8. Repair of Ischemic Injury by Pluripotent Stem Cell Based Cell Therapy without Teratoma through Selective Photosensitivity

    Directory of Open Access Journals (Sweden)

    Seung-Ju Cho

    2015-12-01

    Full Text Available Stem-toxic small molecules have been developed to induce selective cell death of pluripotent stem cells (PSCs to lower the risk of teratoma formation. However, despite their high efficacies, chemical-based approaches may carry unexpected toxicities on specific differentiated cell types. Herein, we took advantage of KillerRed (KR as a suicide gene, to selectively induce phototoxicity using visible light via the production of reactive oxygen species. PSCs in an undifferentiated state that exclusively expressed KR (KR-PSCs were eliminated by a single exposure to visible light. This highly selective cell death in KR-PSCs was exploited to successfully inhibit teratoma formation. In particular, endothelial cells from KR-mPSCs remained fully functional in vitro and sufficient to repair ischemic injury in vivo regardless of light exposure, suggesting that a genetic approach in which KR is expressed in a tightly controlled manner would be a viable strategy to inhibit teratoma formation for future safe PSC-based therapies.

  9. Ovarian Mature Cystic Teratoma Containing Multiple Mobile

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hyun Sun; Yoon, Seong Eon; Lee, Young Hwan; Kim, Hye Won; Yoon, Kwon Ha [Wonkwang University Hospital, Iksan (Korea, Republic of); Park, Seong Hoon [Asan Medical Center, Seoul (Korea, Republic of)

    2006-12-15

    A 48-year-old woman was admitted to our hospital with a palpable mass in her lower abdomen. A left ovarian, cystic mass containing multiple mobile globules was seen on CT and MR images. The outer portion of the globules showed fat components on CT and fat-saturated T1-weighted MR images. Ultrasonography showed multiple echogenic, mobile globules with some sound attenuation and hyper echoic lines and dots within the cystic mass, which corresponded with the presence of lipid globules and hair shafts of ovarian mature cystic teratoma, respectively

  10. Ovarian Mature Cystic Teratoma Containing Multiple Mobile

    International Nuclear Information System (INIS)

    Cho, Hyun Sun; Yoon, Seong Eon; Lee, Young Hwan; Kim, Hye Won; Yoon, Kwon Ha; Park, Seong Hoon

    2006-01-01

    A 48-year-old woman was admitted to our hospital with a palpable mass in her lower abdomen. A left ovarian, cystic mass containing multiple mobile globules was seen on CT and MR images. The outer portion of the globules showed fat components on CT and fat-saturated T1-weighted MR images. Ultrasonography showed multiple echogenic, mobile globules with some sound attenuation and hyper echoic lines and dots within the cystic mass, which corresponded with the presence of lipid globules and hair shafts of ovarian mature cystic teratoma, respectively

  11. An ovarian teratoma of late Roman age.

    Science.gov (United States)

    Armentano, Núria; Subirana, Mercè; Isidro, Albert; Escala, Oscar; Malgosa, Assumpció

    2012-12-01

    We report here a very unusual pelvic calcification recovered from the remains of a 30-40-year-old woman found at the late Roman period archeological site of La Fogonussa (Lleida, Catalonia). Although differential diagnoses for calcifications of the pelvis are complicated in archeological contexts, the precise localization, macroscopic features, and the presence of teeth along with part of a small bone led us to identify this case as an ovarian teratoma, based upon gross observations and computerized tomography (CT). Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Bone histomorphometry in de novo renal transplant recipients indicates a further decline in bone resorption 1 year posttransplantation.

    Science.gov (United States)

    Evenepoel, Pieter; Behets, Geert J; Viaene, Liesbeth; D'Haese, Patrick C

    2017-02-01

    Renal transplantation is believed to have a major impact on bone health. The present prospective observational bone biopsy study aimed to define the natural history of bone histomorphometry parameters in contemporaneous de novo renal transplant recipients. Paired bone biopsies were performed at the time of transplantation and at one-year posttransplantation in an unselected cohort of 36 patients referred for deceased kidney replacement. Parameters of mineral metabolism and circulating bone turnover markers were monitored as well. Static parameters of bone formation and especially bone resorption being already low-normal in the majority of patients at the time of renal transplantation, further declined during the first posttransplant year. However, interindividual variation was substantial, and significance was reached only for bone resorption parameters. Bone mineralization and trabecular bone volume were within the normal range at the time of transplantation (83.3% and 91.7% of graft recipients, respectively) and showed little change one-year posttransplantation. Changes in osteoclast number were paralleled by changes in circulating tartrate-resistant acid phosphatase 5b levels. Finally, cumulative glucocorticoid dose, but not the posttransplantation parathyroid hormone level, associated with trabecular bone loss. Thus, the impact of renal transplantation on bone histomorphometry is limited with only bone resorption, being already low at the time of transplantation, showing a further decline. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  13. Congenital intracerebral teratoma: a rare differential diagnosis in newborn hydrocephalus

    International Nuclear Information System (INIS)

    Storr, U.; Rupprecht, T.; Bornemann, A.; Ries, M.; Beinder, E.; Boewing, B.; Harms, D.

    1997-01-01

    Cogenital hydrocephalus is caused by a broad spectrum of underlying disorders. In the majority of cases it is due to aqueductal stenosis and other distinct congenital anomalies, like Arnold-Chiari malformation. Nevertheless, in the differential diagnosis rare conditions such as cerebral malignancies must also be considered. We present two cases of congenital intracerebral teratoma as a differential diagnosis in congenital obstructive hydrocephalus. A teratoma is suggested when a rapidly growing hydrocephalus with a central calcified and vascularized mass is found sonographically. Regular cerebral structures using cannot be detected. Early diagnosis in such cases is of clinical importance as the prognosis of congential intracerebral teratoma is generally very poor. (orig.)

  14. Congenital intracerebral teratoma: a rare differential diagnosis in newborn hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Storr, U. [Landratsamt Neuburg-Schrobenhausen, Gesundheitsamt, Neuburg an der Donau (Germany)]|[Hospital for Sick Children, Erlangen-Nuernberg Univ., Nuernberg (Germany); Rupprecht, T. [Hospital for Sick Children, Erlangen-Nuernberg Univ., Nuernberg (Germany); Bornemann, A. [Inst. for General Pathology, Erlangen-Nuernberg Univ., Nuernberg (Germany); Ries, M. [Hospital for Sick Children, Erlangen-Nuernberg Univ., Nuernberg (Germany); Beinder, E. [Dept. of Obstetrics and Gynecology, Erlangen-Nuernberg Univ., Nuernberg (Germany); Boewing, B. [Hospital for Sick Children, Erlangen-Nuernberg Univ., Nuernberg (Germany); Harms, D. [Hospital for Sick Children, Erlangen-Nuernberg Univ., Nuernberg (Germany)

    1997-03-01

    Cogenital hydrocephalus is caused by a broad spectrum of underlying disorders. In the majority of cases it is due to aqueductal stenosis and other distinct congenital anomalies, like Arnold-Chiari malformation. Nevertheless, in the differential diagnosis rare conditions such as cerebral malignancies must also be considered. We present two cases of congenital intracerebral teratoma as a differential diagnosis in congenital obstructive hydrocephalus. A teratoma is suggested when a rapidly growing hydrocephalus with a central calcified and vascularized mass is found sonographically. Regular cerebral structures using cannot be detected. Early diagnosis in such cases is of clinical importance as the prognosis of congential intracerebral teratoma is generally very poor. (orig.)

  15. A Case of Post Obstructive Pneumonia Complicating Mature Teratoma

    African Journals Online (AJOL)

    Mediastinal teratomas are rare germ cell tumors in children accounting for only 4.3% of all germ cell tumours.[1] Mature ... from two or more embryonic layers. Patients ... dehydrogenase and beta human chorionic gonadotropins were normal.

  16. Paraneoplastic syndromes revealing ovarian teratoma in young and ...

    African Journals Online (AJOL)

    Paraneoplastic syndromes revealing ovarian teratoma in young and menopausal women: report of two cases. Majdouline Boujoual, Ihsan Hakimi, Farid Kassidi, Youssef Akhoudad, Nawal Sahel, Adil Rkiouak, Mohamed Allaoui, Hafsa Chahdi, Mohamed Oukabli, Jaouad Kouach, Driss Rahali Moussaoui, Mohamed ...

  17. Fetal intracranial neoplasm–not always a teratoma!

    Directory of Open Access Journals (Sweden)

    Hirsig LE

    2016-08-01

    Full Text Available Although congenital intracranial tumors are very rare, it is important to know the differential diagnosis and distinguishing features of the different disease processes in order to accurately diagnosis and appropriately treat these patients in the neonatal period. We present a case of a rare congenital craniopharyngioma detected in a fetus on prenatal imaging. Teratoma is the most common congenital intracranial tumor. Hence this tumor was initially labelled as a teratoma, which is a pitfall that should be avoided.

  18. Giant Primary Retroperitoneal Teratoma in an Adult: A Case Report

    Directory of Open Access Journals (Sweden)

    Poonam Mathur

    2010-01-01

    Full Text Available Teratomas are bizarre neoplasms derived from embryonic tissues that are typically found only in the gonadal and sacrococcygeal regions of adults. Retroperitoneal teratomas are rare and present challenging management options. We report here the case of a histologically unusual retroperitoneal tumor detected on computed tomography during the workup of abdominal pain in a 32-year-old male. The evaluation and treatment of this condition and a review of the literature are included in this paper.

  19. Mature cystic teratoma of the pancreas in a child

    International Nuclear Information System (INIS)

    Yu, C.W.; Liu, K.L.; Li, Y.W.; Lin, W.C.

    2003-01-01

    A cystic pancreatic tumour is rare in a child and a mature cystic teratoma of the pancreas is even rarer. This is the first demonstration of the CT appearance of such a tumour in a child. We present a 2-year-old boy who presented with a palpable abdominal mass. Abdominal CT revealed a huge cystic mass in the upper abdomen. Pathology disclosed a mature cystic teratoma originating from the pancreas. (orig.)

  20. Concurrent split cord malformation and teratoma: dysembryology, presentation, and treatment.

    Science.gov (United States)

    Babu, Ranjith; Reynolds, Renee; Moreno, Jessica R; Cummings, Thomas J; Bagley, Carlos A

    2014-02-01

    Split cord malformation (SCM) is a rare form of spinal dysraphism in which the spinal cord is divided in the sagittal plane, forming a double neural tube. In addition to being associated with a variety of malformations, SCM may occur with spinal cord tumors, with only exceptional cases involving teratomas. As only eight patients with a teratoma associated with SCM have been reported, their presentation characteristics and treatment are currently unclear. We review the literature of all patients with SCM with concurrent spinal teratoma, discuss the potential dysembryology, and report the first case of SCM with concurrent spinal teratoma in an elderly patient. The mean age of those with concurrent SCM and teratomas was 39.4 years, with 55.6% occurring in females. The lumbar spine was the most frequent location for teratomas (66.7%), with the Type II malformation more commonly occurring with these tumors (75%). The duration of symptoms varied widely, ranging from 1 month to 5 years, with the average duration being nearly 2 years. Back pain (87.5%) and lower extremity weakness (75%) were the most common presenting symptoms. As SCM may be associated with progressive neurological deterioration and teratomas can contain immature or malignant components, surgery should be attempted with the goal of gross total resection. Nonetheless, in patients with a concurrent tumor and spinal dysraphism, spinal teratomas should be considered in the differential diagnosis. Gross total resection of these lesions may be safely achieved even in the presence of SCM using intraoperative electrophysiologic monitoring. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Is gliomatosis peritonei derived from the associated ovarian teratoma?

    Science.gov (United States)

    Kwan, Man-Yee; Kalle, Wouter; Lau, Gene T C; Chan, John K C

    2004-06-01

    Gliomatosis peritonei, a rare condition that occurs almost exclusively in the setting of ovarian immature teratoma, is characterized by the occurrence of nodules of mature glial tissues in the peritoneum. It is controversial whether glial tissues are derived from maturation of the associated teratomatous tissue that has implanted in the peritoneum, or glial differentiation of subperitoneal stem cells. In this study, we employed the unique genetic characteristics of ovarian teratomas (often with a duplicated set of maternal chromosomes and thus homozygous at many polymorphic microsatellite loci) versus normal tissues (heterozygous pattern due to presence of maternal and paternal genetic materials) to investigate the origin of gliomatosis peritonei. DNA samples were extracted from microdissected paraffin-embedded tissues, including the glial implants, the associated ovarian teratomas, and normal tissues, to determine their patterns of microsatellite loci in a multiplex polymerase chain reaction system. Two cases were not informative because the ovarian teratoma showed a heterozygous microsatellite pattern. In the 5 informative cases, the normal tissues showed a heterozygous pattern in the microsatellite loci, the associated teratomas showed a homozygous pattern, and the glial tissues showed a heterozygous pattern. Thus, gliomatosis peritonei is genetically unrelated to the associated teratoma but is probably derived from nonteratomatous cells, such as through metaplasia of submesothelial cells.

  2. Endoscopic Resection of Skull Base Teratoma in Klippel-Feil Syndrome through Use of Combined Ultrasonic and Bipolar Diathermy Platforms

    Directory of Open Access Journals (Sweden)

    Justin A. Edward

    2017-01-01

    Full Text Available Klippel-Feil syndrome (KFS is associated with numerous craniofacial abnormalities but rarely with skull base tumor formation. We report an unusual and dramatic case of a symptomatic, mature skull base teratoma in an adult patient with KFS, with extension through the basisphenoid to obstruct the nasopharynx. This benign lesion was associated with midline palatal and cerebral defects, most notably pituitary and vertebrobasilar arteriolar duplications. A multidisciplinary workup and a complete endoscopic, transnasal surgical approach between otolaryngology and neurosurgery were undertaken. Out of concern for vascular control of the fibrofatty dense tumor stalk at the skull base and need for complete teratoma resection, we successfully employed a tissue resection tool with combined ultrasonic and bipolar diathermy to the tumor pedicle at the sphenoid/clivus junction. No CSF leak or major hemorrhage was noted using this endonasal approach, and no concerning postoperative sequelae were encountered. The patient continues to do well now 3 years after tumor extirpation, with resolution of all preoperative symptoms and absence of teratoma recurrence. KFS, teratoma biology, endocrine gland duplication, and the complex considerations required for successfully addressing this type of advanced skull base pathology are all reviewed herein.

  3. BAX-mediated cell death affects early germ cell loss and incidence of testicular teratomas in Dnd1(Ter/Ter) mice.

    Science.gov (United States)

    Cook, Matthew S; Coveney, Douglas; Batchvarov, Iordan; Nadeau, Joseph H; Capel, Blanche

    2009-04-15

    A homozygous nonsense mutation (Ter) in murine Dnd1 (Dnd1(Ter/Ter)) results in a significant early loss of primordial germ cells (PGCs) prior to colonization of the gonad in both sexes and all genetic backgrounds tested. The same mutation also leads to testicular teratomas only on the 129Sv/J background. Male mutants on other genetic backgrounds ultimately lose all PGCs with no incidence of teratoma formation. It is not clear how these PGCs are lost or what factors directly control the strain-specific phenotype variation. To determine the mechanism underlying early PGC loss we crossed Dnd1(Ter/Ter) embryos to a Bax-null background and found that germ cells were partially rescued. Surprisingly, on a mixed genetic background, rescued male germ cells also generated fully developed teratomas at a high rate. Double-mutant females on a mixed background did not develop teratomas, but were fertile and produced viable off-spring. However, when Dnd1(Ter/Ter) XX germ cells developed in a testicular environment they gave rise to the same neoplastic clusters as mutant XY germ cells in a testis. We conclude that BAX-mediated apoptosis plays a role in early germ cell loss and protects from testicular teratoma formation on a mixed genetic background.

  4. Effective treatment for malignant mediastinal teratoma.

    Science.gov (United States)

    Parker, D; Holford, C P; Begent, R H; Newlands, E S; Rustin, G J; Makey, A R; Bagshawe, K D

    1983-12-01

    Primary malignant mediastinal teratoma is a rare tumour previously regarded as inevitably fatal. In a series of eight male patients with a mean age of 24 years five remain alive and well. All patients showed raised serum concentrations of human chorionic gonadotrophin or alpha fetoprotein. The patients were treated with intermittent combination chemotherapy that included cisplatin. Six patients responded to chemotherapy with a fall in human chorionic gonadotrophin or alpha fetoprotein to near normal levels and they then had radical excision of the remaining tumour. Living malignant tumour was found in four of the specimens and these patients received postoperative chemotherapy. One patient died after eight months and the remaining five patients are alive and well 13-136 months after the start of treatment. The two patients who did not undergo surgery died at one month and 15 months. Intermittent combination chemotherapy and carefully timed radical excision of these tumours would appear to have produced better results than have been reported in other series.

  5. Thoracic Epidural Teratoma: Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Jennifer L. Quon

    2014-01-01

    Full Text Available Purpose Spinal teratomas comprise a rare subset of spinal cord tumors, and here, we describe an even rarer childhood thoracic extradural-intracanalicular teratoma. The clinical presentation, management, and pathophysiology of these tumors are reviewed to promote recognition and guide treatment of these lesions. Methods We report the case of a 21-month-old boy who presented with marked spasticity, as well as failure to ambulate and meet motor milestones. Additionally, we provide a literature review of spinal teratomas, including their clinical presentation, work-up, pathophysiology, and underlying genetics. Results An MRI of the spine revealed a large dorsal epidural tumor extending from T3 to T10 with heterogeneous contrast enhancement and severe spinal cord compression. The tumor was resected revealing a cystic mass with tissue resembling hair, muscle, as well as cartilage; pathology confirmed the diagnosis of teratoma. Gross total resection was achieved, and the child eventually gained ambulatory function. Conclusions Given that spinal teratomas are rare entities that can present with significant neurologic compromise, they must remain on clinicians’ differentials. Unfortunately, the exact origin of these tumors remains inconclusive and requires further investigation.

  6. Mesenteric teratoma associated with acute perforated appendicitis in a 2-year-old girl

    Directory of Open Access Journals (Sweden)

    Jihoon Jang

    2016-07-01

    Full Text Available Mesenteric teratoma is a rare tumor, with few cases reported in the literature. Because mesenteric teratomas have no specific signs or symptoms, their clinical manifestations depend on their size and location. This report describes a mesenteric teratoma associated with acute perforated appendicitis in a 2-year-old girl who presented with abdominal pain and high grade fever.

  7. Mature Teratoma Associated with Bilateral Ovarian Carcinosarcoma - Accidental Association or Etiopathogenetic Determinism? - Case Report.

    Science.gov (United States)

    Birla, Rodica; Catanescu, Elena-Roxana; Caragui, Andrei; Constantinoiu, Silviu

    2016-01-01

    Carcinosarcoma is a rare form of ovarian cancer with mixed origin, and its association with mature teratoma is extremely rare. We present the case of patient T. M. aged 67, admitted into our clinic on the 15/05/2016, F.O. 4877 for the increase of the abdominal volume. On admission, the patient was afebrile, conscious, cooperative, cardio-respiratory balanced, having the abdomen distended in volume, sharp dullness in the flanks, positive wave sign bioumoral within normal limits except: uric acid = 6.64 mg / dL, serum glucose = 113.7 mg / dl, serum total proteins = 8.65 g / dl, the albumin / globulin subunit, CRP 33.63 mg / l, sideremia 51 ug / dl, CA 125 = 588.4 IU. Abdominal ultrasound: high volume fluid and multiple perihepatic formations and multiple formations with cystic transformation in the abdomen and pelvis. CT exam describes multiple tissular masses localized intraperitoneal in the abdominal-pelvic region, sheath fluid effusion, infiltrative, with mass effect on the digestive lumens, without visible CT obstruction. Surgical treatment consisted in evacuation of the ascites fluid, excision of the tumoral lumps situated in the great omentum, omentectomy, excision of the lumps of the gastrocolic ligament, bilateral ovariectomy and hysterectomy. Postoperative simple evolution. Histopathology confirmed the diagnosis of bilateral ovarian carcinosarcoma associated with tridermic mature teratoma (presence of brain tissue areas associated with cartilage, transitional type epithelium, tubal type epithelium, endometrial stroma type and fatty tissue). IHC confirms the compatibility with the diagnosis of ovarian carcinosarcoma (mixed malignant Mullerian tumor). The patient followed adjuvant polichemotherapy. The association of teratoma with carcinosarcomatoase elements confers a poor prognosis case. Celsius.

  8. Monophasic teratoma of the ovarian remnant in a bitch.

    Science.gov (United States)

    Rota, A; Tursi, M; Zabarino, S; Appino, S

    2013-04-01

    An exploratory laparotomy on a mixed-breed bitch of an estimated age of 5 years revealed that she had undergone ovariectomy in the past, but a cystic structure was present in the area of the right ovary and a whitish mass, approximately 3 cm in diameter, in the area of the left ovary. These structures were removed together with an apparently normal uterus. Histological examination of the cyst showed a thin layer of connective tissue, while the left ovarian mass revealed ovarian tissue and highly differentiated nervous tissue, confirmed through immunohistochemistry. A presumptive diagnosis of mature ovarian teratoma was made. Although teratomas generally contain recognizable elements from more than one of the three germ cell layers, they can also be monophasic, when there is only one germ layer component. Ovarian teratomas are rare in the dog and never before have been reported in an ovarian fragment. © 2012 Blackwell Verlag GmbH.

  9. Cystic struma ovarii: a rare ovarian teratoma

    International Nuclear Information System (INIS)

    Malik, B.A.; Ali, Z.

    2011-01-01

    Struma ovarii is a unique variant of the monodermal teratomas of the ovary, which is entirely composed of thyroid tissue. It is a rare tumor which comprises 1-4% of all benign ovarian tumors. The age of presentation ranges between 6 to 74 years. It is a benign tumor and is usually unilateral. Clinical symptoms such as pelvic mass, abdominal pain and ascities occur in one third of patients, whereas rarely patients may present with pseudo-meig syndrome. Ultrasonography and computed tomography show a solid cystic mass. Histologically benign struma ovarii contain thyroid follicles of variable sizes filled with colloid. A 53 years old female presented with one month history of lower abdominal pain. The clinical and radiological findings suggested a left ovarian mass measuring 7 x 5 x 3 cm. An exploratory laparotomy was performed and the left ovarian mass was resected. The specimen was sent to AFIP for anatomical diagnosis. On gross examination, the specimen consisted of left ovary measuring 14 x 12 x 6.5 cm and weighing 527 grams. External surface of the ovary showed many multinodular areas with few cystic areas. Largest of the cyst measured 8 x 7 x 4 cm. On opening all the cysts contained yellowish watery fluid. Maximum thickness of the largest cyst wall was 0.5 cm. The solid area in the ovary measured 5 x 4 x 3 cm. On serial slicing the solid areas had whitish variegated appearance and areas of gritty hard consistency. No fallopian tube was found. Representative sections from different areas of the specimen were prepared. Histologically, the sections revealed effacement of the normal ovarian architecture by mature thyroid follicles containing colloid (Fig. 2). Some areas showed degenerated thyroid tissue with hyalinization and areas of calcification. More than 50% of the material examined contained thyroid tissue. No evidence of atypia was seen in the material examined. (author)

  10. Rupture of Ovarian Mature Cystic Teratoma: Computerized Tomography Findings

    International Nuclear Information System (INIS)

    Sebastia, C.; Sarrias, M.; Sanchez-Aliaga, E.; Quiroga, S.; Boye, R.; Alvarez-Castells, A.

    2004-01-01

    We present computed tomography findings of three cases of intraperitoneal rupture of ovarian mature cystic teratoma. Acute-phase radiological findings include presence of intraabdominal liquid, infiltration of mesenteric fat and calcified pelvic mass which also showed interior fatty content. Chronic-phase findings include infiltration of peritoneal fat, as well as increase in the size of adjacent ganglion due to chronic inflammatory response to histologically verified foreign bodies. Differential diagnoses between chronic and acute intraperitoneal ruptures of mature teratoma have been reviewed. (Author)

  11. Testicular teratoma, mimicking a simple testicular cyst, in an infant.

    Science.gov (United States)

    Di Renzo, Dacia; Persico, Antonello; Sindici, Giulia; Lelli Chiesa, Pierluigi

    2013-09-01

    Prepubertal testicular tumors are rare, and teratoma is the second most frequent histologic type. Its typical features are those of a hard and painless scrotal mass at clinical examination, and nonhomogeneous, echoic, often with calcifications at ultrasonography. Rare but reported is the atypical presentation as a transilluminating scrotal mass, due to the presence of some internal cystic areas, detectable at ultrasonography. We report the case of an infant with a transilluminating scrotal mass, mimicking at ultrasonography and surgery a simple, fully liquid cyst, which the pathologic examination revealed to be mature cystic testicular teratoma. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Progression from an Immature Teratoma with Miliary Gliomatosis Peritonei to Growing Teratoma Syndrome with Nodular Gliomatosis Peritonei

    Directory of Open Access Journals (Sweden)

    Yuh-Lin Hsieh

    2009-04-01

    Full Text Available A 4½-year-old girl presented with an incompletely resected, huge, immature abdominal teratoma, elevated serum alpha-fetoprotein (AFP, and numerous miliary gliomatosis peritonei (GP. Two courses of chemotherapy resulted in normalization of her AFP level and marked tumor shrinkage. Further chemotherapy was interrupted by complications. During treatment for these complications, ascites increased and the tumor enlarged, but serum AFP remained within the normal range. Second-look surgery revealed that the tumor had changed histologically to a mature teratoma, and GP had enlarged to nodular size, causing massive ascites. The still incompletely resected, growing mature teratoma was reduced with inter-feron. Nodular GP and ascites slowly regressed with interferon use, and finally disappeared after several months. One residual mass thought to be GP was reduced by gamma-knife surgery 3 years later.

  13. Evaluation of posttransplantation soluble CD30 for diagnosis of acute renal allograft rejection.

    Science.gov (United States)

    Pelzl, Steffen; Opelz, Gerhard; Daniel, Volker; Wiesel, Manfred; Süsal, Caner

    2003-02-15

    Posttransplantation measurement of soluble CD30 (sCD30) may be useful for identifying kidney graft recipients at risk of impending graft rejection in the early posttransplantation period. We measured plasma sCD30 levels and evaluated the levels in relation to the diagnosis of rejection. Receiver operating characteristic curves demonstrated that on posttransplantation days 3 to 5, sCD30 allowed a differentiation of recipients who subsequently developed acute allograft rejection (n=25) from recipients with an uncomplicated course (n=20, Pacute tubular necrosis in the absence of rejection (n=11, P=0.001) (area under the receiver operating characteristic curve 0.85, specificity 91%, sensitivity 72%). sCD30 measured on posttransplantation days 3 to 5 offers a noninvasive means for differentiating patients with impending acute allograft rejection from patients with an uncomplicated course or with acute tubular necrosis.

  14. Teratoma That Making Aganglionic Colon Loop in an Infant: A Case Report

    Directory of Open Access Journals (Sweden)

    Ilhan Ciftci

    2017-12-01

    Full Text Available A case of an usual occurrence of mature teratoma in in ovary and sacrococcygeal region is reported with a review of the literature. Retroperitoneal teratomas are rare in children. Teratomas are composed of multiple tissues foreign to the organ or site in which they arise. Teratomas showing organoid development of intestine are extremely rare. We described the macroscopic and histopathology findings of an unusual case of teratoma with aganglionic colonic loops in a three months old child in retroperitoneal region. [J Contemp Med 2017; 7(4.000: 407-411

  15. Adenocarcinomas arising from primary retroperitoneal mature teratomas: CT and MR imaging

    International Nuclear Information System (INIS)

    Wang, Li-Jen; Wong, Yon-Cheong; Chu, Sheng-Hsien; Ng, Kwai-Fong

    2002-01-01

    An adenocarcinoma arising from mature teratoma is one form of teratoma with malignant transformation. It is extremely rare but highly malignant. The authors report two patients with adenocarcinomas arising from primary retroperitoneal teratomas. The CT and MRI findings of the tumors are presented with emphasis on imaging features implying the presence of malignant transformation and differing from those of pure benign mature teratoma. Correct diagnosis of the presence of malignant transformation from a benign mature teratoma can be made as early as possible by awareness of the imaging features. (orig.)

  16. Squamous cell carcinoma arising in a mature cystic teratoma

    Directory of Open Access Journals (Sweden)

    Gupta Vishwanath

    2009-04-01

    Full Text Available Two cases of squamous cell carcinoma (SCC arising in a mature cystic teratoma (MCT are being discussed for their rarity and pattern of infiltration of tumor cells in the stroma (alpha mode, beta mode and gamma mode, which is a key factor in deciding the prognosis and patient survival.

  17. Sacrococcygeal teratoma: Clinical characteristics and long-term ...

    African Journals Online (AJOL)

    Background/Purpose : The excision of sacrococcygeal teratoma (SCT) may be associated with significant long-term morbidity for the child. We reviewed our experience with SCT in a tertiary health care facility in a developing country with particular interest on the long-term sequelae. Methods : Between January 1990 and ...

  18. Sexual function after treatment for sacrococcygeal teratoma during childhood

    NARCIS (Netherlands)

    Kremer, M.E.; Derikx, J.P.; Peeters, A.; Kuile, M.M. Ter; Baren, R. van; Heij, H.A.; Wijnen, M.H.W.A.; Wijnen, R.M.; Zee, D.C. van der; Heurn, L.W. van

    2016-01-01

    BACKGROUND: Children treated for sacrococcygeal teratoma (SCT) may suffer from sexual dysfunction later in life because of the extended pelvic surgery performed, however, structured evaluations have not been performed yet. METHODS: The Female Sexual Function Index (FSFI), the International Index of

  19. CT findings of overian teratomas : mature versus immature

    International Nuclear Information System (INIS)

    Kim, Jong Chul; Kim, Young Wol

    1996-01-01

    To differentiate mature and immature ovarian teratomas, using CT findings. The CT findings of ten mature ovarian teratomas (in one patient, bilateral) and ten which were immature were compared, using statistical analysis. Images were evaluated for size, margins, architecture, contents (mural nodules, fat, calcification), septa, local invasion and distant metastasis. These findings were compared with pathologic findings. Of the ten mature tumors, nine were well defined and predominantly cystic in internal architecture, and one was mixed. Mural nodules were found in six tumor, fat in all, distinct calcification in seven, and regular septa in three lesions. Of the ten immature humors, eight had irregular margins. Seven were predominantly solid in internal architecture and irregularly enhanced, two were mixed, and one was mainly cystic. Fat was detected in five lesions, indistinct scattered calcification in six, irregular septa in three, and local invasion of distant metastasis in four patients. Compared with mature ovarian teratomas, those that are immature tend to show CT findings of marginal irregularity, solid mass with irregular enhacement, scattered indistinct calcifications, septal irregularity, local invasion or distant metastasis. Our experience suggests that these findings may be helpful in differentiation of mature and immature ovarian teratomas

  20. Intestinal Obstruction due to Bilateral Ovarian Cystic Teratoma in a ...

    African Journals Online (AJOL)

    Teratoma is the most common ovarian tumour associated with pregnancy. The complications in pregnancy include torsion, rupture and malignant transformation mimicking ovarian carcinoma. Its association with intestinal obstruction is uncommon. Case: A 35 year old gravida 5 para 4 woman with 18 week gestation was ...

  1. Sacrococcygeal teratoma: 10-year experience in upper Egypt ...

    African Journals Online (AJOL)

    Purpose To evaluate our experience with 45 patients with sacrococcygeal teratoma (SCT) in our community (upper Egypt) over a period of 10 years between 2001 and 2011 and determine the outcome of the management and recommendations for treatment strategies. Patients and methods A retrospective study was ...

  2. Magnetic Resonance Imaging Verification of a Case of Sacrococcygeal Teratoma.

    Science.gov (United States)

    Dedushi, Kreshnike; Kabashi, Serbeze; Mucaj, Sefedin; Ramadani, Naser; Hoxhaj, Astrit; Shatri, Jeton; Hasbahta, Gazmend

    2016-08-01

    Although rare, sacrococcygeal teratoma is the most common congenital neoplasm, occurring in 1 in 40,000 infants. Approximately 75% of affected infants are female. The aim of the present study was to correlate ultrasonography and magnetic resonance imaging (MRI) findings in patients with fetal sacrococcygeal teratoma. Three pregnant women in 27th week of gestation underwent fetal MRI after ultrasonography examination, with findings suggestive for fetal sacrococcygeal teratoma. Tumor size, location, extent and content were evaluated both by MRI and ultrasonography. Findings regarding tumor location, size and content were similar for both methods. There was a large well-circumscribed mixed, cystic/solid oval mass, originating from right sacro-gluteal region and projecting into the amniotic cavity, 132 × 110 × 76 mm in size. The mass had a heterogeneous appearance. The T1 high signal suggested fat component of the tumor, while T1 and T2 hypointense components suggested calcified/bony components. There was also T1 hypointense component consistent with cystic and fluid component. The imaging findings were characteristic for sacrococcygeal teratoma. There was not obvious lumbar or thoracic spinal involvement. There was no gross intrapelvic or abdominal extension, and even sacrum and coccyx appeared deformed. The amount of amniotic fluid was increased. MRI was superior to ultrasonography in the evaluation of the exact tumor extent, accurately demonstrating pelvic involvement in all of the three cases. Fetal MRI has shown to be a valuable adjunct to obstetric sonography in the evaluation of fetal sacrococcygeal teratoma, because of its higher accuracy in the determination of tumors extent and content, playing a significant role in the therapeutic planning and increasing the chances of cure for these fetuses.

  3. Magnetic Resonance Imaging Verification of a Case of Sacrococcygeal Teratoma

    Science.gov (United States)

    Dedushi, Kreshnike; Kabashi, Serbeze; Mucaj, Sefedin; Ramadani, Naser; Hoxhaj, Astrit; Shatri, Jeton; Hasbahta, Gazmend

    2016-01-01

    Although rare, sacrococcygeal teratoma is the most common congenital neoplasm, occurring in 1 in 40,000 infants. Approximately 75% of affected infants are female. The aim of the present study was to correlate ultrasonography and magnetic resonance imaging (MRI) findings in patients with fetal sacrococcygeal teratoma. Three pregnant women in 27th week of gestation underwent fetal MRI after ultrasonography examination, with findings suggestive for fetal sacrococcygeal teratoma. Tumor size, location, extent and content were evaluated both by MRI and ultrasonography. Findings regarding tumor location, size and content were similar for both methods. There was a large well-circumscribed mixed, cystic/solid oval mass, originating from right sacro-gluteal region and projecting into the amniotic cavity, 132 × 110 × 76 mm in size. The mass had a heterogeneous appearance. The T1 high signal suggested fat component of the tumor, while T1 and T2 hypointense components suggested calcified/bony components. There was also T1 hypointense component consistent with cystic and fluid component. The imaging findings were characteristic for sacrococcygeal teratoma. There was not obvious lumbar or thoracic spinal involvement. There was no gross intrapelvic or abdominal extension, and even sacrum and coccyx appeared deformed. The amount of amniotic fluid was increased. MRI was superior to ultrasonography in the evaluation of the exact tumor extent, accurately demonstrating pelvic involvement in all of the three cases. Fetal MRI has shown to be a valuable adjunct to obstetric sonography in the evaluation of fetal sacrococcygeal teratoma, because of its higher accuracy in the determination of tumors extent and content, playing a significant role in the therapeutic planning and increasing the chances of cure for these fetuses. PMID:28983369

  4. Squamous cell carcinoma arising in mature cystic teratoma of ovary

    Directory of Open Access Journals (Sweden)

    Ranu Patni

    2014-01-01

    Full Text Available Squamous cell carcinoma of the ovary is a rare condition and usually arises in mature cystic teratoma (MCT or dermoid cyst of the ovary. The reported incidence of malignant transformation in MCT is approximately 2%. A case of squamous cell carcinoma arising in a dermoid cyst of the ovary presenting at an early stage is presented here. A 53-year-old postmenopausal lady, presented with the complaint of pain in right lower abdomen since one month and a large complex abdomino-pelvic mass on examination and investigations. Final histopathology was reported as squamous cell carcinoma of left ovary arising from dermoid cyst and a benign dermoid cyst in the right ovary. The patient was assigned to squamous cell carcinoma of the ovary arising in a mature cystic teratoma, surgical stage Ic2. In view of the poor prognosis, adjuvant chemotherapy was started.

  5. Profound nephrotic syndrome in a patient with ovarian teratoma

    Directory of Open Access Journals (Sweden)

    Abdallah Jeroudi

    2013-01-01

    Full Text Available The nephrotic syndrome (NS has been associated with a variety of malignancies in a number of reports in the literature, but has been reported in only nine cases associated with ovarian neoplasms. Membranous nephropathy is the most common glomerular pathology causing the NS in patients with solid tumors. There has been only one report of an ovarian neoplasm associated with minimal change disease (MCD. We describe the case of a 36-year-old woman who presented with the NS secondary to biopsy-proven MCD, likely secondary to mature ovarian teratoma. Treatment by tumor removal and prednisone led to remission of the NS. To the best of our knowledge, this is the first report of an ovarian teratoma and the second report of an ovarian neoplasm associated with MCD.

  6. Malignant Cervical Teratoma in an Adult Presenting with Impending Airway Obstruction

    Directory of Open Access Journals (Sweden)

    Mohd Rashid Lukman

    2005-07-01

    Full Text Available Extragonadal teratomas and germ cell tumours are uncommon. Most teratomas of the head and neck present in the paediatric age group. Occurrence of such tumours in an adult is extremely rare and, to date, less than 40 cases have been reported in the literature. We report a case of a young man presenting with impending airway obstruction secondary to a malignant teratoma of the neck.

  7. Bilateral ovarian teratoma presenting with a clinical picture of acute abdomen

    Directory of Open Access Journals (Sweden)

    Massimiliano Rocchietti March

    2012-12-01

    Full Text Available We describe the case of a 30-year-old patient with bilateral mature cystic teratoma (MCT of the ovaries. The patient had been complaining of mild abdominal pain for several months that had suddenly become severe. Early diagnosis at the emergency room was acute appendicitis, but definitive diagnosis was bilateral ovarian teratoma. We therefore recommend considering ovarian teratomas in the differential diagnosis of acute abdomen in young women in an emergency care setting.

  8. MR imaging of a mature teratoma in third ventricle: case report

    International Nuclear Information System (INIS)

    Kim, Myung Soon; Sung, Ki Joon; Cho, Mee Yon

    1994-01-01

    Teratoma is very rarely developed in the third ventricle. We report a case of third ventricular mature teratoma in 12-year old boy with headache and precocious puberty. In T1WI and Gd-DTPA enhanced T1WI, the mass in the third ventricle showed mixed signal intensities with signal void and partial contrast enhancement. The tumor was confirmed as a mature teratoma including teeth and fatty tissue

  9. MR imaging of a mature teratoma in third ventricle: case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung Soon; Sung, Ki Joon; Cho, Mee Yon [Wonju College of Medicine, Yonsei University, Wonju (Korea, Republic of)

    1994-01-15

    Teratoma is very rarely developed in the third ventricle. We report a case of third ventricular mature teratoma in 12-year old boy with headache and precocious puberty. In T1WI and Gd-DTPA enhanced T1WI, the mass in the third ventricle showed mixed signal intensities with signal void and partial contrast enhancement. The tumor was confirmed as a mature teratoma including teeth and fatty tissue.

  10. Teratoma with intraventricular free fat on CT. Case report

    Energy Technology Data Exchange (ETDEWEB)

    Miura, Naohisa; Fuchinoe, Tokuro; Yahagi, Yasuji; Nakamura, Toshihiko [Toshima Municipal Hospital of Metropolitan Tokyo (Japan)

    1983-11-01

    Intracranial fat-containing congenital tumors are characterized by negative absorption values on computed tomography(CT). We are reporting a case of teratoma with intraventricular free fat diagnosed preoperatively by CT. The case is a 19-year-old female who was admitted to our hospital because of continuous severe headache, nausea and vomiting. At the time of admission, her physical and neurological examination was negative except for bilateral papilledema. CT demonstrated marked enlargement of the right lateral ventricle. In addition, there was negative absorption value (-90 H.U.), suggesting free fat, within right frontal horn layering above the CSF with a fluid level. Metrizamide ventriculography demonstrated complete obstruction and revealed an irregular shadow defect at the right foramen of Monro. At surgery, yellowish cheese-like material, white hair was found on the surface of the CSF. Tumor arose from the floor of the right foramen of Monro and extended upward. The patient made an uneventful recovery and was discharged 17 days after surgery. Intraventricular free fat is likely that to be released from the teratoma cyst ruptured spontaneously when the patient complained of severe headache 40 days prior to admission. There have been several published reports of the CT appearances of intracranial fat-containing tumors, however, teratoma with intraventricular free fat is very rare. It was concluded that fat-containing tumors should be highly suspected, when negative absorption values were found on CT.

  11. Pentalogy of Cantrell: Complete expression with mediastinal teratoma

    Directory of Open Access Journals (Sweden)

    Michał Błaszczyński

    2015-08-01

    Full Text Available Pentalogy of Cantrell (POC is a rare, and often fatal congenital disorder that is characterized by a pentad consisting of ectopia cordis, omphalocele, sternal cleft, congenital diaphragmatic hernia, and various intra-cardiac defects. Although the hallmark of POC consists of these five anomalies, only a handful of cases have been reported with the full spectrum of this disorder. This case report presents a full term female with complete expression of POC and a mediastinal teratoma. Two days after birth, this infant underwent correction of the omphalocele and diaphragmatic defect, with repositioning of the cardiac apex within the thoracic cavity. Three months later surgical correction of the intra-cardiac defects took place. At initiation of cardiac by-pass a mediastinal mass at the superior cavopulmonary junction was identified and excised. This mass on histopathology was a teratoma, which makes this case unique as the occurrence of POC and mediastinal teratoma is unreported. This infant has survived the series of corrective surgeries, and is now functioning well. Conclusion: when POC is suspected further investigation for associated anomalies is required for a planned multidisciplinary surgical approach combined with neonatal intensive care to afford the opportunity for a successful outcome.

  12. Prediction of acute renal allograft rejection in early post-transplantation period by soluble CD30.

    Science.gov (United States)

    Dong, Wang; Shunliang, Yang; Weizhen, Wu; Qinghua, Wang; Zhangxin, Zeng; Jianming, Tan; He, Wang

    2006-06-01

    To evaluate the feasibility of serum sCD30 for prediction of acute graft rejection, we analyzed clinical data of 231 patients, whose serum levels of sCD30 were detected by ELISA before and after transplantation. They were divided into three groups: acute rejection group (AR, n = 49), uncomplicated course group (UC, n = 171) and delayed graft function group (DGF, n = 11). Preoperative sCD30 levels of three groups were 183 +/- 74, 177 +/- 82 and 168 +/- 53 U/ml, respectively (P = 0.82). Significant decrease of sCD30 was detected in three groups on day 5 and 10 post-transplantation respectively (52 +/- 30 and 9 +/- 5 U/ml respectively, P sCD30 values on day 5 post-transplantation (92 +/- 27 U/ml vs. 41 +/- 20 U/ml and 48 +/- 18 U/ml, P sCD30 levels on day 10 post-transplantation were virtually similar in patients of three groups (P = 0.43). Receiver operating characteristic (ROC) curve demonstrated that sCD30 level on day 5 post-transplantation could differentiate patients who subsequently suffered acute allograft rejection from others (area under ROC curve 0.95). According to ROC curve, 65 U/ml may be the optimal operational cut-off level to predict impending graft rejection (specificity 91.8%, sensitivity 87.1%). Measurement of soluble CD30 on day 5 post-transplantation might offer a noninvasive means to recognize patients at risk of impending acute graft rejection during early post-transplantation period.

  13. Intramedullary spinal immature teratoma: resolution of quadriplegia following resection in a 4-week-old infant.

    Science.gov (United States)

    Nickols, Hilary Highfield; Chambless, Lola B; Carson, Robert P; Coffin, Cheryl M; Pearson, Matthew M; Abel, Ty W

    2010-12-01

    Intramedullary spinal cord teratomas are rare entities in infants. Management of these lesions is primarily surgical, with outcome dependent on rapid surgical decompression and complete gross-total tumor resection. The lesions are typically of the mature type, with immature teratomas displaying unique pathological features. The authors report a case of an extensive intramedullary immature teratoma in an infant with resolution of quadriplegia following gross-total radical resection. At the 1-year follow-up, there was radiographic evidence of tumor, and surgical reexploration yielded portions of immature teratoma and extensive gliosis.

  14. Liver Enzymes and the Development of Posttransplantation Diabetes Mellitus in Renal Transplant Recipients

    NARCIS (Netherlands)

    Klaassen, Gerald; Corpeleijn, Eva; Deetman, Nicole P E; Navis, Gerjan J; Bakker, Stephan J L; Zelle, Dorien M

    BACKGROUND: Posttransplantation diabetes mellitus (PTDM) is common in renal transplant recipients (RTR), increasing the risk of graft failure, cardiovascular disease, and mortality. Early detection of a high risk for PTDM is warranted. Because liver function and liver fat are involved, we

  15. A Case of Death Secondary to Phrenic Nerve Palsy after Huge Mediastinal Teratoma 
Resection in Newborn

    Directory of Open Access Journals (Sweden)

    Yuanda CHENG

    2015-08-01

    Full Text Available Neonatal teratomas, not common in clinical, are often some case reports, female more than male, most are benign. It can occur anywhere of body midline; sacrococcygeal teratoma is the most common and the second most frequent site of extragonadal teratomas is mediastinum. Benign is more commom and malignant is very rarely seen. Completely surgical resection is the main and effective treatment. This review reports a case of neonatal teratoma, which is complicated with a fatal phrenic nerve palsy after surgery.

  16. Gastric teratoma in a 6-month-old boy | Wildbrett | African Journal of ...

    African Journals Online (AJOL)

    Gastric teratomas are very rare embryonal neoplasms, accounting for 2.6% of all perinatal diagnosed germ cell tumours. About 85% are well-differentiated mature lesions and about 15% are immature tumours with the potential of malignant transformation. The recommended therapy for gastric teratomas is surgical excision.

  17. Orbito-Ocular Teratoma: A Case Report | Akabe | Nigerian Journal of ...

    African Journals Online (AJOL)

    Orbital teratomas are rare. This is a report of a case of orbito-ocular teratoma with malignant transformation in a seventeen-day-old girl. Treatment was by exenteration. The baby was lost to follow-up shortly after discharge and so could not have a prosthesis fitted (Nig J Surg Res 2000; 2:155-157) KEY WORDS:

  18. Intestinal duplication and retroperitoneal teratoma in child hoof: a case report; Duplicacao intestinal e teratoma retroperitoneal na infancia: relato de caso

    Energy Technology Data Exchange (ETDEWEB)

    Atzingen, Augusto Castelli Von; Bazzano, Felix Carlos Ocariz; Tiburzio, Nicolas Biagione; Grande, Rogerio Mendes; Juntolli Netto, Joao Diniz [Universidade do Vale do Sapucai (UNIVAS), Pouso Alegre, MG (Brazil). Hospital das Clinicas Samuel Libanio (HCSL)]. E-mail: augvonatzingen@bol.com.br; augvonatzingen@hotmail.com

    2007-07-01

    The authors present a case of intestinal duplication and retroperitoneal teratoma in a 7-year-old patient with evident mass and abdominal pain to explain; that it was submitted to study conventional X-ray, ultrasonography, computed tomography and subsequent exploiting laparotomia. The anatomopathological study verified intestinal duplication and ripe teratoma. In the existent medical literature it was not found any similar case. (author)

  19. MR diagnosis of infantile teratoma in sacrococcygeal region

    International Nuclear Information System (INIS)

    Xu Jianchang; Gao Zhiqin; Lou Jianghua

    2009-01-01

    Objective: To discuss the MR manifestations of infantile teratoma in sacrococcygeal region and to evaluate the diagnostic value of MR. Methods: Retrospective analysis was adopted on the MR results of 15 affected infants. Results: The tumors in 2 cases located in hip, which is mainly cystic, circular or ellipse shaped with septum and fat signal can be seen. The wall and septum of the cysts can be reinforced in contrast enhanced imaging. The tumor in 1 case located total in pelvic cavity, presenting cystic and solitary mixed signal. The solitary part, cystic wall and septum can be obviously unequally reinforced in contrast enhanced imaging. In the rest 12 cases, the most parts of tumors located in pelvic cavity and small parts in hip presenting mainly cystic and partly solitary mixed signal. The solitary part, cystic wall and septum can be reinforced in contrast enhanced imaging. Conclusion: MR can accurately display the location and shape of teratoma in sacrococcygeal region and is contribute to diagnose and differentiate benign or malignant lesion, in order to help clinician to choose operation method. (authors)

  20. Upper abdominal teratomas in infants: radiological findings and importance of the vascular anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Hart, Jonathan; Mazrani, Waseem; McHugh, Kieran [Great Ormond Street Hospital for Children, Radiology Department, London (United Kingdom); Jones, Niall; Kiely, Edward M. [Great Ormond Street Hospital for Children, Surgery Department, London (United Kingdom); Sebire, Neil J. [Great Ormond Street Hospital for Children, Pathology Department, London (United Kingdom)

    2008-07-15

    Primary upper abdominal teratomas are extremely rare tumours, most commonly arising in infants. The radiological literature relating to them is sparse. Surgical resection is difficult due to distortion of the vascular anatomy. To reassess the value of preoperative imaging with specific reference to the presence/absence of typical features of teratoma, anatomical location and adjacent vascular anatomy. The histopathology database was used to identify infants with upper abdominal teratoma. Pathological, surgical and radiological data were reviewed. The search of the database identified 12 infants (10 girls, 2 boys) with an abdominal/retroperitoneal teratoma during the period 1993 to 2006. All teratomas were benign. In the majority of infants, typical radiological features of teratoma were demonstrated (fat, calcium). Identification of the major abdominal vessels on CT scan (most commonly the inferior vena cava) was not possible in all infants. Distortion (and commonly encasement) of the adjacent major abdominal vessels was usually evident. Upper abdominal teratomas in infants have typical radiological features. Preoperative delineation of the major vascular anatomy is often imprecise. Significant distortion of vascular anatomy was present in all infants and awareness of this feature impacts on surgical planning. (orig.)

  1. Upper abdominal teratomas in infants: radiological findings and importance of the vascular anatomy

    International Nuclear Information System (INIS)

    Hart, Jonathan; Mazrani, Waseem; McHugh, Kieran; Jones, Niall; Kiely, Edward M.; Sebire, Neil J.

    2008-01-01

    Primary upper abdominal teratomas are extremely rare tumours, most commonly arising in infants. The radiological literature relating to them is sparse. Surgical resection is difficult due to distortion of the vascular anatomy. To reassess the value of preoperative imaging with specific reference to the presence/absence of typical features of teratoma, anatomical location and adjacent vascular anatomy. The histopathology database was used to identify infants with upper abdominal teratoma. Pathological, surgical and radiological data were reviewed. The search of the database identified 12 infants (10 girls, 2 boys) with an abdominal/retroperitoneal teratoma during the period 1993 to 2006. All teratomas were benign. In the majority of infants, typical radiological features of teratoma were demonstrated (fat, calcium). Identification of the major abdominal vessels on CT scan (most commonly the inferior vena cava) was not possible in all infants. Distortion (and commonly encasement) of the adjacent major abdominal vessels was usually evident. Upper abdominal teratomas in infants have typical radiological features. Preoperative delineation of the major vascular anatomy is often imprecise. Significant distortion of vascular anatomy was present in all infants and awareness of this feature impacts on surgical planning. (orig.)

  2. Diagnosis and management of an immature teratoma during ovarian stimulation: a case report

    Directory of Open Access Journals (Sweden)

    Douay-Hauser Nathalie

    2011-11-01

    Full Text Available Abstract Introduction The discovery of a mature teratoma (dermoid cyst of the ovary during ovarian stimulation is not a rare event. Conversely, we could not find any reported cases of immature teratoma in such a situation. Clinical and ultrasound arguments for this immature form are scarcely or poorly evaluated. Case Presentation We describe the case of a 31-year-old Caucasian woman with primary infertility, who developed an immature teratoma during an in vitro fertilization ovarian stimulation cycle. Conclusions Ultrasound signs of an atypical cyst during ovarian stimulation allowed us to adopt a careful medical attitude and to adapt the required surgical oncological treatment.

  3. Sacrococcygeal teratoma in a female newborn with clinical features of trisomy 13: a case report from Central Africa

    Directory of Open Access Journals (Sweden)

    Lubala TK

    2015-12-01

    Full Text Available Toni Kasole Lubala,1,2 Olivier Mukuku,1 Mick Pongombo Shongo,1,2 Augustin Mulangu Mutombo,1 Nina Lubala,1 Oscar Numbi Luboya,1 Prosper Lukusa-Tshilobo3 1Department of Paediatrics, Faculty of Medicine, 2Center for Human Genetics, Faculty of Medicine, University of Lubumbashi, Lubumbashi, 3Department of Paediatrics and Centre for Human Genetics, University Hospital, University of Kinshasa, Kinshasa, Democratic Republic of Congo Introduction: The objective of this report is to describe the first patient presenting clinical features of trisomy 13 in association with a sacrococcygeal teratoma. Case presentation: We present the case of a Congolese female infant born with bilateral cleft lip and palate, hypotelorism, microcephaly, and capillary hemangioma on her face. She presented with a large sacrococcygeal mass (15.0 cm ×12.0 cm ×5.0 cm with a cystic consistency and a positive transillumination. Conclusion: This observation suggests that overexpression of certain genes on chromosome 13 may lead to tumor formation from remnant cells of Hensen’s node. Keywords: Patau syndrome, Hensens’s Node, sacrococcygeal, teratoma  

  4. An interesting case of isolated pancreatic teratoma: lessons to learn.

    Science.gov (United States)

    Razman, J; Azlanudin, A; Eyad, A J; Zahiah, M; Das, S

    2012-11-01

    Mature cystic teratomas of the pancreas are extremely rare tumours encountered in day-to-day clinical practice. Only few cases have been reported to date involving all age groups. The management, diagnosis and evaluation of this tumor are questionable, with definitive diagnosis taking place intra-operatively. We hereby report the case in a 30 year-old-male who presented with newly diagnosed diabetes mellitus and during the follow up he was noted to have elevated liver enzymes clinically, he was asymptomatic. The computerized tomography revealed a retropancreatic mass and pushing the mesenteric veins anteriorly. The mass was hypodense in nature and there was presence of calcification. Although the patient was asymptomatic, the decision for resecting the mass was made in view of the size and possibility of malignancy. In conclusion, considering the size and approximity of the mass to the pancreas, Whipple procedure's is the most appropriate approach although the histological diagnosis has not been established preoperatively.

  5. Congenital Cervical Teratoma: Anaesthetic Management (The EXIT Procedure

    Directory of Open Access Journals (Sweden)

    Ferruh Bilgin

    2009-01-01

    Full Text Available Ex utero intrapartum treatment (EXIT is a procedure performed during caesarean section with preservation of fetal-placental circulation, which allows the safe handling of fetal airways with risk of airways obstruction. This report aimed at describing a case of anaesthesia for EXIT in a fetus with cervical teratoma. A 30-year-old woman, 70 kg, 160 cm, gravida 2, para 1, was followed because of polyhydramniosis diagnosed at 24 weeks′ gestation. During a routine ultrasonographic examination at 35 weeks′ gestation, it was noticed that the fetus had a tumoral mass on the anterior neck, the mass had cystic and calcified components and with a size of was 10 x 6 x5 cm. The patient with physical status ASA I, was submitted to caesarean section under general anaesthesia with mechanically controlled ventilation for exutero intrapartum treatment (EXIT. Anaesthesia was induced in rapid sequence with fentanyl, propofol and rocuronium and was maintained with isoflurane in 2.5 at 3 % in O 2 and N 2 O (50%. After hysterotomy, fetus was partially released assuring uterus-placental circulation, followed by fetal laryngoscopy and tracheal intuba-tion. The infant was intubated with an uncuffed, size 2.5 endotracheal tube. Excision of the mass was performed under general anaesthesia. After surgical intervention, on the fourth postoperative day, the infant was extubated and the newborn was discharged to the pediatric neonatal unit and on the seventh day postoperatively to home without complications. Major recommendations for EXIT are maternal-fetal safety, uterine relaxation to maintain uterine volume and uterus-placental circulation, and fetal immobility to help airway handling. We report one case of cervical teratoma managed successfully with EXIT procedure.

  6. An unusual mature thyroid teratoma on CT and {sup 99}Tcm scintigraphy imaging in a child

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu-Zhen; Li, Wen-Hua; Li, Yu-Hua; Gao, Yu [Xin Hua Hospital, Shanghai Jiaotong University School of Medicine, Department of Radiology, Shanghai (China); Zhu, Ming-Jie [Xin Hua Hospital, Shanghai Jiaotong University School of Medicine, Department of Radiology, Shanghai (China); Xin Hua Hospital, Shanghai Jiaotong University School of Medicine, Department of Pathology, Shanghai (China)

    2010-11-15

    We report the imaging findings of a mature thyroid teratoma in a 5-year-old girl. Nuclear imaging showed a decrease in {sup 99}Tcm uptake in the right lobe of the thyroid gland. CT scan showed a slightly lobulated soft-tissue mass without calcification, fat or cystic components. Histological analysis showed that the tumor was composed of mature neural tissue, cartilaginous, and epithelial elements. This case study provides new insights into the CT appearance of mature thyroid teratomas. (orig.)

  7. Intestinal duplication and retroperitoneal teratoma in child hoof: a case report

    International Nuclear Information System (INIS)

    Atzingen, Augusto Castelli Von; Bazzano, Felix Carlos Ocariz; Tiburzio, Nicolas Biagione; Grande, Rogerio Mendes; Juntolli Netto, Joao Diniz

    2007-01-01

    The authors present a case of intestinal duplication and retroperitoneal teratoma in a 7-year-old patient with evident mass and abdominal pain to explain; that it was submitted to study conventional X-ray, ultrasonography, computed tomography and subsequent exploiting laparotomia. The anatomopathological study verified intestinal duplication and ripe teratoma. In the existent medical literature it was not found any similar case. (author)

  8. Primary retroperitoneal teratoma and crossed fused renal ectopia with turner's syndrome -a case report-

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yun Jung; Hong, Ki Ung [St. Francisco General Hospital, New York (United States)

    1988-02-15

    In 1938, Turner described a clinical entity in phenotype females characterized by sexual infantilism, congenital webbed neck and cubitus valgus. After then, the occurrence of renal anomalies in patients with Turner's syndrome has been recognized. Associated crossed fused renal ectopia is very rare. Primary retroperitoneal teratoma is also rare and usually during childhood. The authors report a case of primary retroperitoneal teratoma and crossed fused renal ectopia with Turner's syndrome (mosaic type). The clinical, pathological and radiographical findings are reviewed.

  9. Primary retroperitoneal teratoma and crossed fused renal ectopia with turner's syndrome -a case report-

    International Nuclear Information System (INIS)

    Kim, Yun Jung; Hong, Ki Ung

    1988-01-01

    In 1938, Turner described a clinical entity in phenotype females characterized by sexual infantilism, congenital webbed neck and cubitus valgus. After then, the occurrence of renal anomalies in patients with Turner's syndrome has been recognized. Associated crossed fused renal ectopia is very rare. Primary retroperitoneal teratoma is also rare and usually during childhood. The authors report a case of primary retroperitoneal teratoma and crossed fused renal ectopia with Turner's syndrome (mosaic type). The clinical, pathological and radiographical findings are reviewed

  10. A Case of Extragonadal Teratoma in the Pouch of Douglas and Literature Review.

    Science.gov (United States)

    Kakuda, Mamoru; Matsuzaki, Shinya; Kobayashi, Eiji; Yoshino, Kiyoshi; Morii, Eiichi; Kimura, Tadashi

    2015-01-01

    Mature cystic teratoma is a germ cell tumor of the ovaries and is often observed in clinical practice. However, extragonadal teratomas are rare tumors and have been reported outside the ovaries, (e.g., in the greater omentum). The mechanism underlying the development of extragonadal teratomas remains unknown. We encountered a case of extragonadal teratoma in the pouch of Douglas that appeared to be a parasitic dermoid cyst. From our experience and the literature review, we discuss the potential mechanism leading to the development of extragonadal teratomas. A 41-year-old nonpregnant woman was referred to our department due to myoma and anemia. A 4-cm asymptomatic mass in the pouch of Douglas was observed, and the patient was diagnosed with ovarian mature cystic teratoma. She underwent laparoscopic surgery, and intraoperative findings revealed that the fallopian tube was injured and torn, and a residual small ovary was observed in the left side of the ovary. A tumor measuring approximately 4 cm observed in the pouch of Douglas was extracted without rupturing. The tumor was diagnosed as a parasitic dermoid cyst by macroscopic and histopathological findings. Auto-amputation could be the underlying mechanism that leads to an isolated parasitic dermoid cyst in the pouch of Douglas. Copyright © 2015 AAGL. Published by Elsevier Inc. All rights reserved.

  11. Effect of H-2 complex on the growth of embryo-derived teratomas in mice

    International Nuclear Information System (INIS)

    Taya, C.; Moriwaki, K.

    1986-01-01

    Seven-day-old embryos of several H-2 congenic strains were transplanted under the kidney capsules of syngeneic adult recipients to determine the genetic factors(s) governing the in vivo growth of embryo-derived teratomas. A.TH(H-2t2) and A.TL(H-2t1) strains showed significantly greater tumor weights than A.BY(H-2b) and A.SW(H-2s) strains. The A(H-2a) strain was intermediate in tumor size. A comparison of the genic constitution of the H-2 complex in each congenic strain suggested that the H-2D locus and/or its distal regions affected the growth of embryo-derived teratomas. The teratoma induced in the B10.A(H-2a) strain was smaller than that in the A(H-2a) strain, indicating that the genetic background of the A strain is favorable for teratoma growth. Histological observations demonstrated that the existence of embryonal carcinoma cells was necessary for the growth of teratomas. A radiation-sensitive immunological factor in the recipient probably plays a role in stimulating teratoma growth

  12. Mature teratoma in association with neural tube defect (occipital encephalocele): series of four cases and review of the literature.

    Science.gov (United States)

    Goyal, Nishant; Singh, Pankaj Kumar; Kakkar, Aanchal; Sharma, Meher Chand; Mahapatra, Ashok Kumar

    2012-01-01

    Both occipital encephalocele and teratomas are midline congenital malformations. Encephalocele is a form of neural tube defect in which there is a congenital defect of the cranium through which occurs a protrusion of brain matter or meninges, while teratoma is a tumor derived from all three germ layers. The association between occipital encephalocele and teratoma has not been reported to date. In the present study, the authors present a series of four such cases. Copyright © 2012 S. Karger AG, Basel.

  13. Diagnosis and surgical management of malignant ovarian teratoma in a green iguana (Iguana iguana).

    Science.gov (United States)

    Bel, Lucia; Tecilla, Marco; Borza, Gabriel; Pestean, Cosmin; Purdoiu, Robert; Ober, Ciprian; Oana, Liviu; Taulescu, Marian

    2016-07-19

    Ovarian tumors in reptiles are uncommonly reported in the literature and for green iguanas previously reported cases include teratomas, one adenocarcinoma and one papillary cystadenocarcinoma. The present report is the first of a malignant ovarian teratoma in a green iguana. Complete and detailed pathological features, differential diagnosis and surgical management of malignant ovarian teratoma are discussed in this paper. A 9-year-old intact female green iguana (Iguana iguana) with a clinical history of persistent anorexia and progressive abdominal distension was referred to the surgery department. On physical examination, a presumptive diagnosis of follicular stasis was established. Radiographic evaluation showed a large radioopaque mass within the abdomen, which was visible both in latero-lateral and ventro-dorsal exposures. Abdominal ultrasonography showed a large intra-abdominal mass, with numerous cyst-like structures filled with liquid and a heterogeneous aspect with hypoechoic areas. Exploratory laparatomy was thus suggested and the mass was removed surgically. The histologic findings of the neoplasm were consistent with those of ovarian malignant teratoma. Surgical excision of the mass in our case was considered curative and after a follow-up period of 6 months the animal has recovered completely. A malignant ovarian teratoma has not been previously reported in green iguana and should be included in the list of differential diagnosis of ovarian tumors in this species. This report will contribute to a better understanding of the pathology of this rare tumor in green iguanas.

  14. Anti-N-methyl-D-aspartate receptor encephalitis with an imaging-invisible ovarian teratoma: a case report.

    Science.gov (United States)

    Abdul-Rahman, Zainab M; Panegyres, Peter K; Roeck, Margareta; Hawkins, David; Bharath, Jude; Grolman, Paul; Neppe, Cliffe; Palmer, David

    2016-10-24

    Anti-N-methyl-D-aspartate receptor encephalitis is a recently discovered disease entity of paraneoplastic limbic encephalitis. It largely affects young women and is often associated with an ovarian teratoma. It is a serious yet treatable condition if diagnosed early. Its remedy involves immunotherapy and surgical removal of the teratoma of the ovaries. This case of anti-N-methyl-D-aspartate receptor encephalitis involves an early surgical intervention with bilateral oophorectomy, despite negative imaging evidence of a teratoma. A 25-year-old white woman with anti-N-methyl-D-aspartate receptor encephalitis presented with behavioral changes and seizures that were confirmed to be secondary to anti-N-methyl-D-aspartate receptor encephalitis. She required an admission to our intensive care unit for ventilator support and received a number of immunological therapies. Multiple imaging investigations showed no evidence of an ovarian teratoma; she had a bilateral oophorectomy 29 days after admission. Ovarian histology confirmed the presence of a teratoma with neuronal cells. A few days after the operation she began to show signs of improvement and, apart from mild short-term memory loss, she returned to normal function. Our patient is an example of teratoma-associated anti-N-methyl-D-aspartate receptor encephalitis, in which the teratoma was identified only microscopically. Her case highlights that even with negative imaging evidence of a teratoma, ovarian pathology should still be considered and explored.

  15. Sacrococcygeal Teratoma Presenting with Vaginal Discharge and Polyp in an Infant.

    Science.gov (United States)

    Ladenhauf, Hannah N; Brandtner, M Georgina; Schimke, Christa; Ardelean, Mircia A; Metzger, Roman

    2018-06-01

    Sacrococcygeal teratoma accounts for the most common solid tumor in neonates. Because of improved technology, 50%-70% of cases can be diagnosed antenatally during routine ultrasound screenings. If not diagnosed antenatally, clinical findings at birth are distinct in most cases including a palpable or visible mass. We report an unusual case of a 1-year-old girl who presented with persistent vaginal discharge leading to diagnosis of a mucosal polypoid lesion of the vagina, ultimately revealing a hidden sacrococcygeal teratoma. We suggest thorough investigation of all infants who present with purulent discharge and recurrent vaginal mass; sacrococcygeal teratoma should routinely be considered as a differential diagnosis. Copyright © 2017 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  16. Mature Teratoma of the Petrous Bone with Extension into the Cerebellopontine Angle: Case Report

    Science.gov (United States)

    Khan, Nickalus; Klimo, Paul; Harreld, Julie; Armstrong, Gregory T.; Michael, L. Madison

    2013-01-01

    Purpose Intracranial teratomas in children involving lateral structures such as the petrous portion of the temporal bone are very uncommon. The authors report a case of a petrous teratoma with significant extension into the cerebellopontine angle with brainstem compression. Case Report An 11-year-old girl presented left-sided facial weakness. Computed tomography (CT) demonstrated a multiloculated lesion expanding the labyrinthine structures in the left petrous temporal bone including the vestibule, semicircular canals, and cochlea, with extension to the left cerebellopontine angle via the expanded left internal auditory canal. The tumor was resected via a transtemporal approach with no evidence of recurrence at nearly 2 years. Conclusion Complete resection should be the primary treatment for these tumors to minimize the risk of recurrence. To the authors' knowledge, this is the first case report of a mature teratoma originating in the petrous bone with extension into the cerebellopontine angle. PMID:24294566

  17. Unusual fast-growing ovarian cystic teratoma during pregnancy presenting with intracystic fat "floating balls" appearance.

    Science.gov (United States)

    Donnadieu, Anne Claire; Deffieux, Xavier; Le Ray, Camille; Mordefroid, Marie; Frydman, René; Fernandez, Hervé

    2006-12-01

    A large ovarian cyst was diagnosed at 22 weeks' of gestation in a 32-year-old woman. The ultrasonographic appearance of the ovarian cyst was unusual with multiple mobile, spherical echogenic structures floating in the cystic mass, called intracystic "fat balls." Right adnexectomy was performed by laparotomy at 28 weeks' of gestation, because of rapid growth and overall size exceeding 20 cm. Pathological examination confirmed ovarian cystic teratoma. Usually, dermoid cysts are slow-growing, even in premenopausal women. The exact mechanism related to the fast growth during pregnancy is unknown. It could be related to an unusual pattern of estrogen (E)/P receptors expression in the cystic teratoma. This case shows that a fast-growing, mature ovarian cystic teratoma may occur during pregnancy.

  18. Cervical mature teratoma 17 years after initial treatment of testicular teratocarcinoma: report of a late relapse

    Directory of Open Access Journals (Sweden)

    Alavion Mina

    2007-01-01

    Full Text Available Abstract Background Late relapses of testicular germ cell tumor are uncommon. We report a case of cervical mature teratoma appeared 17 years after treatment of testicular teratocarcinoma. Case presentation A 20- year- old patient underwent left sided orchiectomy followed by systemic therapy and retroperitoneal residual mass resection in 1989. He remained in complete remission for 200 months. In 2005 a huge left supraclavicular neck mass with extension to anterior mediastinum appeared. Radical surgical resection of the mass was performed and pathologic examination revealed mature teratoma. Conclusion This is one of the longest long-term reported intervals of a mature teratoma after treatment of a testicular nonseminoma germ cell tumor. This case emphasizes the necessity for follow up of testicular cancer throughout the patient's life.

  19. Malignant Transformation in a Mature Teratoma with Metastatic Deposits in the Omentum: A Case Report

    Directory of Open Access Journals (Sweden)

    Shramana Mandal

    2012-01-01

    Full Text Available Malignant transformation of a mature cystic teratoma (MCT is a very rare complication with an incidence of 0.17–2%;. The most common form of malignant transformation of the MCT is squamous cell carcinoma. Other tumors arising in MCT include basal cell carcinoma, sebaceous tumor, malignant melanoma, adenocarcinoma, sarcoma, and neuroectodermal tumor. However malignant transformation with metastatic deposits in the omentum is extremely rare. The present case highlights the rarity of the occurrence of an omental deposits in a case of mature cystic teratoma with malignant transformation.

  20. Reversible paraneoplastic encephalomyelitis as the presenting feature of ovarian teratoma: A clinicopathological correlate

    Directory of Open Access Journals (Sweden)

    Rajappa Senthil

    2007-01-01

    Full Text Available Paraneoplastic encephalomyelitis (PEM is a well-characterized neurological syndrome. Its association with ovarian teratoma is rare. A young lady presented with features suggestive of encephalomyelitis with predominant cerebellar syndrome. Magnetic resonance imaging brain was normal. Cerebrospinal fluid showed lymphocytic pleocytosis. Computerized tomography scan of the pelvis revealed a complex left ovarian cyst. With a clinical diagnosis of PEM she underwent a left salpingo-oopherectomy. This was followed by total recovery of the PEM in two weeks. The histopathology revealed immature teratoma. The interesting feature was the clinicopathological correlation between the finding of fetal cerebellar tissue in the tumor and the PEM with predominant cerebellar features.

  1. Analysis of clinical features and treatment in mature teratomas at pineal region

    Directory of Open Access Journals (Sweden)

    QI Gui-jun

    2012-04-01

    Full Text Available Surgical treatment through occipital tentorium of cerebellum approach was performed in nine cases of mature teratoma at the pineal region. Diagnosis was confirmed by postoperative pathological examination. No perioperative death occurred. Surgery-related complications (visual difficulties, visual field defects, seizures were seen in 4 cases. All cases were followed for 3 months-7 years (mean 3.70 years. The mature teratoma at the pineal region are more common in male children. The main clinical manifestations are intracranial hypertension and ataxia. Neurosurgical treatment may provide satisfactory outcome.

  2. Histological and clinical findings in patients with post-transplantation and classical encapsulating peritoneal sclerosis: A European multicenter study

    NARCIS (Netherlands)

    J. Latus (Joerg); S.M. Habib (Meelad); D. Kitterer (Daniel); M.R. Korte (Mario); C. Ulmer (Christoph); P. Fritz (Peter); S. Davies (Simon); M. Lambie (Mark); M.D. Alscher (M. Dominik); M.G.H. Betjes (Michiel); S. Segerer (Stephan); N. Braun (Niko)

    2014-01-01

    textabstractBackground: Encapsulating peritoneal sclerosis (EPS) commonly presents after peritoneal dialysis has been stopped, either post-transplantation (PT-EPS) or after switching to hemodialysis (classical EPS, cEPS). The aim of the present study was to investigate whether PT-EPS and cEPS differ

  3. GLP-1 Restores Altered Insulin and Glucagon Secretion in Posttransplantation Diabetes

    DEFF Research Database (Denmark)

    Halden, Thea A S; Egeland, Erlend J; Åsberg, Anders

    2016-01-01

    OBJECTIVE: Development of posttransplantation diabetes (PTDM) is characterized by reduced insulin secretion and sensitivity. We aimed to investigate whether hyperglucagonemia could play a role in PTDM and to examine the insulinotropic and glucagonostatic effects of the incretin hormone glucagon...... h of infusion, a 2-h hyperglycemic clamp (fasting plasma glucose + 5 mmol/L) was established. Five grams of arginine was given as an intravenous bolus 10 min before termination of the clamp. RESULTS: Fasting concentrations of glucagon (P = 0.92) and insulin (P = 0.23) were similar between the groups...... to arginine (P = 0.01) but similar glucagon and proinsulin responses compared with control subjects. In the preclamp phase, GLP-1 lowered fasting plasma glucose to the same extent in both groups but reduced glucagon only in PTDM patients. During hyperglycemic clamp, GLP-1 reduced glucagon concentrations...

  4. [Comparison of clinical and histological diagnosis in kidney post-transplantation period].

    Science.gov (United States)

    de Castro, M C; Chocair, P R; Saldanha, L B; Nahas, W; Arap, S; Sabbaga, E; Ianhez, L E

    1998-01-01

    To assess the agreement between clinical and histopathological diagnosis in a renal transplantation center, 40 episodes of acute renal failure were studied. Kidney biopsies were performed at the moment that a clinical diagnosis was made by the staff. Nineteen episodes of acute tubular necrosis (ATN), eighteen episodes of acute cellular rejection (ACR), 2 humoral rejections and 1 acute cyclosporin nephrotoxicity episodes were diagnosed. ATN episodes were confirmed by renal biopsy in 84.21%, ACR episodes in 83.33%, humoral rejections in 100%. Renal biopsy showed ATN in the occurrence of clinical cyclosporin nephrotoxicity. Total agreement was 82.5%. There is a good relationship between clinical and histopathological diagnosis in the post-transplantation period. Diagnostic mistakes occurred mainly when oliguria was present.

  5. Augmenting the post-transplantation growth and survivorship of juvenile scleractinian corals via nutritional enhancement.

    Directory of Open Access Journals (Sweden)

    Tai Chong Toh

    Full Text Available Size-dependent mortality influences the recolonization success of juvenile corals transplanted for reef restoration and assisting juvenile corals attain a refuge size would thus improve post-transplantation survivorship. To explore colony size augmentation strategies, recruits of the scleractinian coral Pocillopora damicornis were fed with live Artemia salina nauplii twice a week for 24 weeks in an ex situ coral nursery. Fed recruits grew significantly faster than unfed ones, with corals in the 3600, 1800, 600 and 0 (control nauplii/L groups exhibiting volumetric growth rates of 10.65 ± 1.46, 4.69 ± 0.9, 3.64 ± 0.55 and 1.18 ± 0.37 mm3/week, respectively. Corals supplied with the highest density of nauplii increased their ecological volume by more than 74 times their initial size, achieving a mean final volume of 248.38 ± 33.44 mm3. The benefits of feeding were apparent even after transplantation to the reef. The corals in the 3600, 1800, 600 and 0 nauplii/L groups grew to final sizes of 4875 ± 260 mm3, 2036 ± 627 mm3, 1066 ± 70 mm3 and 512 ± 116 mm3, respectively. The fed corals had significantly higher survival rates than the unfed ones after transplantation (63%, 59%, 56% and 38% for the 3600, 1800, 600 and 0 nauplii/L treatments respectively. Additionally, cost-effectiveness analysis revealed that the costs per unit volumetric growth were drastically reduced with increasing feed densities. Corals fed with the highest density of nauplii were the most cost-effective (US$0.02/mm3, and were more than 12 times cheaper than the controls. This study demonstrated that nutrition enhancement can augment coral growth and post-transplantation survival, and is a biologically and economically viable option that can be used to supplement existing coral mariculture procedures and enhance reef restoration outcomes.

  6. Teratoma cístico da órbita: estudo clínico patológico: relato de caso Cystic orbital teratoma: clinicopathologic study: case report

    Directory of Open Access Journals (Sweden)

    Iluska Fagundes Andrade

    2008-06-01

    Full Text Available Apresentamos um caso de tumor orbitário congênito de grande tamanho, ocorrendo em criança recém-nascida. A paciente foi submetida a exenteração da órbita e o diagnóstico anatomopatológico foi de teratoma cístico. Os aspectos clínico-patológicos desta rara doença são comentados.We report on a case of an congenital orbital tumor of impressive size, occurring in a newborn. The patient underwent orbital exenteration with a histopathologic diagnosis of cystic teratoma. The clinicopathological aspects of such a rare disease are commented.

  7. Long-term functional sequelae of sacrococcygeal teratoma : a national study in the Netherlands

    NARCIS (Netherlands)

    Derikx, Joep P. M.; De Backer, Antoine; van de Schoot, Leon; Aronson, Daniel C.; de Langen, Zacharias J.; van den Hoonaard, Thelma L.; Bax, Nicolaas M. A.; van der Staak, Frans; van Heurn, L. W. Ernest

    Background: Long-term functional sequelac after resection of sacrococcygeal teratoma (SCT) are relatively common. This study determines the incidence of these sequelae associated clinical variables and its impact on quality of life (QoL). Patients and methods: Patients with SCT treated from 1980 to

  8. [Mediastinal teratoma with malignant transformation of the somatic component. Clinical report].

    Science.gov (United States)

    Gerardo, Rita; Morgado, Carolina; Calvo, Dolores; Pinto, Eugénia; Bravio, Ivan; Castelão, Nelson; Martelo, Fernando

    2009-01-01

    Mediastinal germ cell tumours (M-GCT) are rare forms of neoplasms compared with other tumours of the same location. They are classified in seminomas, malignant non-seminomatous GCT and teratomas. The malignant transformation of the somatic component of the teratoma, with sarcomatous or carcinomatous degeneration, is even more uncommon. We report the clinical case of a 32 year old man who presented with severe chest pain on the right hemithorax. The image exams revealed the existence of a large heterogeneous lesion with a diameter of 7.7 cm, with areas of lipomatous density and a calcic image with the appearance of a tooth, in the right projection of the anterior mediastinum, in the vicinity of the large vessels, compatible with teratoma. The transthoracic biopsy (CT guided) showed morphologic aspects of sarcoma. The patient was operated on with the en bloc resection of the mediastinal mass, right lung, a segment of the pericardium and the thymus. The pathological studies showed a teratoma with malignant transformation of the mesenquimatous component, with muscular differentiation into leiomiosarcoma and rabdomiosarcoma. After surgery, the patient was treated with a scheme of doxorubicin and ifosfamide. The most prominent concepts related to this clinical entity, as well as its treatment, are debated in this article, based on the most recent publications dedicated to the subject.

  9. Growing teratoma syndrome: A case report and review of the literature

    African Journals Online (AJOL)

    teratoma syndrome (GTS) of the ovary was made. She underwent exploratory laparotomy with total abdominal hysterectomy and left salpingo-oophorectomy, and debulking of tumour tissue from the pelvis, Morison's pouch, the diaphragm and the sub-hepatic region. Intraoperatively, deposits were noted on the left ovary and.

  10. Evaluation of chemotherapeutic sequelae and quality of life in survivors of malignant sacrococcygeal teratoma

    NARCIS (Netherlands)

    Kremer, Marijke E B; Derikx, Joep P M; Kremer, Leontien C M; van Baren, Robertine; Heij, Hugo A.; Wijnen, Marc H W A; Wijnen, René M H; van der Zee, David C.; van Heurn, L. W Ernest

    2016-01-01

    Purpose: The impact of chemotherapeutic sequelae on long-term quality of life (QoL) for survivors of malignant sacrococcygeal teratoma (SCT) is unknown. The incidence of chemotherapeutic toxicity in patients treated for malignant SCT and possible effects on the QoL were analyzed. Methods:

  11. Prenatal Diagnosis of Sacrococcygeal Teratoma Using Two and Three-Dimensional Ultrasonography

    Directory of Open Access Journals (Sweden)

    Livia Teresa Moreira Rios

    2012-01-01

    Full Text Available Sacrococcygeal teratoma accounts for half of all fetal tumors, with a prevalence of 1 : 40,000 births. It is believed to originate from pluripotent cells in Hensen's nodule. Although most are benign, they are associated with high morbidity and mortality rates because the fetus develops congestive heart failure and hydrops. Factors leading to poor prognosis include solid components in the mass, and hydrops diagnosed before the 30th week. A case of prenatal sacrococcygeal teratoma diagnosed using B-mode and color Doppler two-dimensional ultrasonography (2DUS is described, in which three-dimensional ultrasonography (3DUS enabled characterization of the extent of fetal lesions and allowed the parents to understand the pathological condition better. A 20-year-old primigravida was referred with a solid mass diagnosed in the lumbosacral spine. Examinations performed at our institution revealed pregnancy of 23 weeks and 4 days, with a female fetus presenting a bulky solid mass with cystic components and calcifications, measuring 7.7×9.1×12.2 cm, starting from the sacral region, with internal flow seen on color Doppler. A new ultrasound confirmed fetal death at 25 weeks and 4 days. Postnatal findings confirmed the diagnosis of sacrococcygeal teratoma. 3DUS can be used in cases of sacrococcygeal teratoma to assess the development of tumor during the prenatal and to allow better understanding of this anomaly by the parents.

  12. Hemorrhage is the most common cause of neonatal mortality in patients with sacrococcygeal teratoma

    NARCIS (Netherlands)

    Kremer, Marijke E. B.; Wellens, Lianne M.; Derikx, Joep P. M.; van Baren, Robertine; Heij, Hugo A.; Wijnen, Marc H. W. A.; Wijnen, René M. H.; van der Zee, David C.; van Heurn, L. W. Ernest

    2016-01-01

    A small percentage of neonates with sacrococcygeal teratoma die shortly after birth from hemorrhagic complications. The incidence of and risk factors associated with hemorrhagic mortality are unknown. In this multicenter study we determined the incidence of early death in neonates born with SCT and

  13. Hemorrhage is the most common cause of neonatal mortality in patients with sacrococcygeal teratoma

    NARCIS (Netherlands)

    Kremer, Marijke E B; Wellens, Lianne M; Derikx, Joep P M; van Baren, Robertine; Heij, Hugo A; Wijnen, Marc H W A; Wijnen, René M H; van der Zee, David C; van Heurn, L W Ernest

    2016-01-01

    BACKGROUND: A small percentage of neonates with sacrococcygeal teratoma die shortly after birth from hemorrhagic complications. The incidence of and risk factors associated with hemorrhagic mortality are unknown. In this multicenter study we determined the incidence of early death in neonates born

  14. Pattern and outcome of childhood teratoma: a 10-year review. | Osifo ...

    African Journals Online (AJOL)

    Ovarian, 23 (43.4%) and sacrococcygeal, 17 (32.1%) sites were frequently involved. Other sites included testicular, 4 (7.5%), retroperitoneal, 4 (7.5%) and renal, 2 (3.8%), while posterior mediastinal, cervical and breast involvement were 1 (1.9%) each. Despite late ... Benign cystic teratomas with malignant elements

  15. Adult-onset intradural spinal teratoma: report of 18 consecutive cases and outcomes in a single center.

    Science.gov (United States)

    Wan, Wei; Yang, Cheng; Yan, Wangjun; Liu, Tielong; Yang, Xinghai; Song, Dianwen; Xiao, Jianru

    2017-07-01

    Eighteen consecutive patients with adult-onset intradural spinal teratoma underwent surgical treatment in our center from 1998 to 2013. Teratoma is defined as a neoplasm composed of elements derived from three germ cell layers (ectoderm, endoderm and mesoderm). Intraspinal teratoma is extremely rare and accounts for 0.2-0.5% of all spinal cord tumors. Moreover, teratoma occurs primarily in neonates and young children. Adult-onset intradural spinal teratoma is even rare. The aim of this study was to discuss the clinical characteristics, diagnosis and therapeutic strategies of adult-onset intradural spinal teratoma. This retrospective study included 18 consecutive adult patients with intradural teratoma who were surgically treated in our center between 1998 and 2013. The clinical features, pathogenesis, diagnostic strategies and surgical outcomes were discussed. Neurological function outcomes were evaluated by the JOA scoring system. Of the 18 included patients, 4 patients received subtotal resection and the other 14 patients received total resection. All the 18 cases were diagnosed with mature teratoma. The mean follow-up period was 79.7 (median 60.5; range 27-208) months. Local recurrence occurred in two of the four patients who underwent subtotal resection and in no patient who underwent total resection. The neurologic status improved in 16 cases and remained unchanged in the other two patients. Adult-onset intradural spinal teratoma is extremely rare. To the best of our knowledge, this is the largest series of patients with this disease. Despite the slow-growth and indolent nature, radical resection remains the recommended treatment to reduce tumor recurrence.

  16. The lived experience of autologous stem cell-transplanted patients: Post-transplantation and before discharge.

    Science.gov (United States)

    Alnasser, Qasem; Abu Kharmah, Salahel Deen; Attia, Manal; Aljafari, Akram; Agyekum, Felicia; Ahmed, Falak Aftab

    2018-04-01

    To explore the lived experience of the patients post-haematopoietic stem cell transplantation and specifically after engraftment and before discharge. Patients post-stem cell transplantation experience significant changes in all life aspects. Previous studies carried out by other researchers focused mainly on the postdischarge experience, where patients reported their perceptions that have always been affected by the life post-transplantation and influenced by their surroundings. The lived experience of patients, specifically after engraftment and prior to discharge (the "transition" phase), has not been adequately explored in the literature. Doing so might provide greater insight into the cause of change post-haematopoietic stem cell transplantation. This study is a phenomenological description of the participants' perception about their lived experience post-haematopoietic stem cell transplantation. The study used Giorgi's method of analysis. Through purposive sampling, 15 post-haematopoietic stem cell transplantation patients were recruited. Data were collected by individual interviews. Data were then analysed based on Giorgi's method of analysis to reveal the meaning of a phenomenon as experienced through the identification of essential themes. The analysis process revealed 12 core themes covered by four categories that detailed patients lived experience post-haematopoietic stem cell transplantation. The four categories were general transplant experience, effects of transplantation, factors of stress alleviation and finally life post-transplantation. This study showed how the haematopoietic stem cell transplantation affected the patients' physical, psychological and spiritual well-being. Transplantation also impacted on the patients' way of thinking and perception of life. Attending to patients' needs during transplantation might help to alleviate the severity of the effects and therefore improve experience. Comprehensive information about transplantation needs

  17. Associations among Epstein-Barr virus subtypes, human leukocyte antigen class I alleles, and the development of posttransplantation lymphoproliferative disorder in bone marrow transplant recipients

    NARCIS (Netherlands)

    Görzer, Irene; Puchhammer-Stöckl, Elisabeth; van Esser, Joost W J; Niesters, Hubert G M; Cornelissen, Jan J

    2007-01-01

    The association between Epstein-Barr virus subtype, human leukocyte antigen class I alleles, and the development of posttransplantation lymphoproliferative disorder was examined in a group of 25 bone marrow transplant recipients. A highly statistically significant correlation was observed between

  18. Isolated Post-Transplantation Lymphoproliferative Disease Involving the Breast and Axilla as Peripheral T-cell Lymphoma

    OpenAIRE

    Hwang, Ji-Young; Cha, Eun Suk; Lee, Jee Eun; Sung, Sun Hee

    2013-01-01

    Post-transplantation lymphoproliferative disorders (PTLDs) are a heterogeneous group of diseases that represent serious complications following immunosuppressive therapy for solid organ or hematopoietic-cell recipients. In contrast to B-cell PTLD, T-cell PTLD is less frequent and is not usually associated with Epstein Barr Virus infection. Moreover, to our knowledge, isolated T-cell PTLD involving the breast is extremely rare and this condition has never been reported previously in the litera...

  19. Comparison of glycemic control and variability in patients with type 2 and posttransplantation diabetes mellitus.

    Science.gov (United States)

    Werzowa, Johannes; Pacini, Giovanni; Hecking, Manfred; Fidler, Catharina; Haidinger, Michael; Brath, Helmut; Thomas, Andreas; Säemann, Marcus D; Tura, Andrea

    2015-01-01

    Posttransplantation diabetes mellitus (PTDM) is a common complication after renal transplantation leading to increased cardiovascular morbidity and mortality. In subjects with type 2 diabetes (T2DM) increased glycemic variability and poor glycemic control have been associated with cardiovascular complications. We therefore aimed at determining glycemic variability and glycemic control in subjects with PTDM in comparison to T2DM subjects. In this observational study we analyzed 10 transplanted subjects without diabetes (Control), 10 transplanted subjects with PTDM, and 8 non-transplanted T2DM subjects using Continuous Glucose Monitoring (CGM). Several indices of glycemic control quality and variability were computed. Many indices of both glycemic control quality and variability were different between control and PTDM subjects, with worse values in PTDM. The indices of glycemic control, such as glucose mean, GRADE and M-value, were similar in PTDM and T2DM, but some indices of glycemic variability, that is CONGA, lability index and shape index, showed a markedly higher (i.e., worse) value in T2DM than in PTDM (P value range: 0.001-0.035). Although PTDM and T2DM subjects showed similar glycemic control quality, glycemic variability was significantly higher in T2DM. These data underscore potential important pathophysiological differences between T2DM and PTDM indicating that increased glycemic variability may not be a key factor for the excess cardiovascular mortality in patients with PTDM. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Low immunosuppressive burden after HLA-matched related or unrelated BMT using posttransplantation cyclophosphamide.

    Science.gov (United States)

    Kanakry, Christopher G; Bolaños-Meade, Javier; Kasamon, Yvette L; Zahurak, Marianna; Durakovic, Nadira; Furlong, Terry; Mielcarek, Marco; Medeot, Marta; Gojo, Ivana; Smith, B Douglas; Kanakry, Jennifer A; Borrello, Ivan M; Brodsky, Robert A; Gladstone, Douglas E; Huff, Carol Ann; Matsui, William H; Swinnen, Lode J; Cooke, Kenneth R; Ambinder, Richard F; Fuchs, Ephraim J; de Lima, Marcos J; Andersson, Borje S; Varadhan, Ravi; O'Donnell, Paul V; Jones, Richard J; Luznik, Leo

    2017-03-09

    The intensive and prolonged immunosuppressive therapy required to prevent or treat graft-versus-host disease (GVHD) after allogeneic blood or marrow transplantation (alloBMT) puts patients at substantial risk for life-threatening infections, organ toxicity, and disease relapse. Posttransplantation cyclophosphamide (PTCy) can function as single-agent GVHD prophylaxis after myeloablative, HLA-matched related (MRD), or HLA-matched unrelated (MUD) donor T-cell-replete bone marrow allografting, obviating the need for additional prophylactic immunosuppression. However, patients who develop GVHD require supplemental treatment. We assessed the longitudinal requirement for immunosuppressive therapy in 339 patients treated with this transplantation platform: 247 receiving busulfan/cyclophosphamide (BuCy) conditioning (data collected retrospectively) and 92 receiving busulfan/fludarabine (BuFlu) conditioning (data collected prospectively). Approximately 50% of MRD patients and 30% of MUD patients never required immunosuppression beyond PTCy. In patients requiring further immunosuppression, typically only 1 to 2 agents were required, and the median durations of systemic pharmacologic immunosuppression for the BuCy MRD, BuFlu MRD, BuCy MUD, and BuFlu MUD groups all were 4.5 to 5 months. For these 4 groups, 1-year probabilities of being alive and off all systemic immunosuppression were 61%, 53%, 53%, and 51% and 3-year probabilities were 53%, 48%, 49%, and 56%, respectively. These data suggest that PTCy minimizes the global immunosuppressive burden experienced by patients undergoing HLA-matched alloBMT.

  1. Multiple genetic variants associated with posttransplantation diabetes mellitus in Chinese Han populations.

    Science.gov (United States)

    Chen, Jie; Li, Lixin; An, Yunfei; Zhang, Junlong; Liao, Yun; Li, Yi; Wang, Lanlan

    2018-03-01

    Posttransplantation diabetes mellitus (PTDM) is a major complication after solid organ transplantation. This study is to investigate the association of nine genetic variant factors and PTDM in Chinese Han patients. HLA-DP (rs3077, rs9277535), HLA-DQ (rs7453920), signal transducer and activator of transcription 4 (STAT4) (rs7574865), IL-28B (rs12979860, rs8099917, and rs12980275), and IL-18 (rs1946518 and rs187238) were investigated in 260 liver transplant recipients (PTDM vs non-PTDM) by high-resolution melting curve analysis. Serum interleukin (IL)-1β, IL-6, IL-8, IL-17, interferon-γ, inducible protein-10, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1b were analyzed by a Bio-Plex suspension array system (Bio-Plex Multiplex Immunoassays, Bio-Rad, Hercules, CA, USA). Signal transducer and activator of transcription 4 (rs7574865) T allele and IL-18 (rs1946518) A allele increase the risk for insulin resistance and PTDM. Recipients with STAT4 (rs7574865) T allele are associated with an increased concentration of IL-1β, interferon-γ, monocyte chemoattractant protein, and macrophage inflammatory protein-1b. The genetic variants of STAT4 (rs7574865) and IL-18 (rs1946518) may be new important markers for PTDM. © 2017 Wiley Periodicals, Inc.

  2. Bilateral ovarian angiosarcoma arising from the mature cystic teratomas – A case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Erik Kudela

    2018-01-01

    Conclusion: This work summarizes the current knowledge in the diagnosis and treatment of angiosarcomas arising in the mature teratomas. Promising results are expected from the trials devoted to antiangiogenic strategies in treatment of aggressive sarcomas.

  3. Identification of patients at risk of acute rejection by pretransplantation and posttransplantation monitoring of soluble CD30 levels in kidney transplantation.

    Science.gov (United States)

    Sengul, Sule; Keven, Kenan; Gormez, Ulku; Kutlay, Sim; Erturk, Sehsuvar; Erbay, Bulent

    2006-04-27

    In this study, we investigated the impact of pre- and posttransplantation sCD30 monitoring on early (acute rejection (AR) risk and analyzed the effect of different immunosuppressive regimens on posttransplantation sCD30 levels in kidney recipients. Fifty patients receiving kidney allograft and 10 healthy donors were included in this retrospective cohort study. Eight patients developed biopsy-proven AR (19%). In pretransplantation samples, patients showed a significantly higher sCD30 than healthy controls. The pretransplantation and posttransplantation (day-15) sCD30 levels were significantly elevated in rejecting patients compared to non-rejecting patients. No significant differences among immunosuppressive regimens were found in posttransplantation sCD30 levels. High pretransplantation and posttransplantation (day 15) sCD30 levels are associated with increased risk of early AR, and sCD30 can be another tool to evaluate immunological risk prior to kidney transplantation. There was no difference in immunosuppressive regimens used in this study on posttransplantation sCD30 levels at the first month.

  4. Gastrointestinal morbidity of adjuvant radiotherapy in stage I malignant teratoma of the testis

    International Nuclear Information System (INIS)

    Hamilton, C.R.; Horwich, A.; Peckham, M.J.; Bliss, J.M.

    1987-01-01

    Between January 1963 and December 1983, 248 patients with stage I teratoma were managed by the Testicular Tumour Unit of the Royal Marsden Hospital (RMH). Before 1979, these patients were treated with adjuvant irradiation to the abdominal and pelvic lymph nodes (142 patients) to a mid-plane dose of 40 Gy in 20 fractions over 4 weeks. In 1979, a surveillance policy was adopted (106 patients) and relapsing patients treated with chemotherapy. By 2 years post-orchidectomy, seven patients (4.9%) in the irradiated group developed duodenal ulceration compared to none in the surveillance group (p = 0.05). A past medical history of duodenal ulcer was a significant risk factor for ulceration after radiotherapy (p = 0.04) whereas a past history of abdominal surgery was not (p = 0.8). It is concluded that adjuvant radiotherapy for stage I teratoma may increase the risk of peptic ulceration. 14 refs.; 1 figure; 4 tabs

  5. Extreme fenestration of the basilar artery associated with cleft palate, nasopharyngeal mature teratoma, and hypophyseal duplication

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, A.; Sawada, A.; Takase, Y.; Kudo, S. [Department of Radiology, Saga Medical School, 5-1-1, Nabeshima, Saga 849-8501 (Japan); Fujita, I. [Department of Pediatrics, Saga Medical School, 5-1-1, Nabeshima, Saga 849-8501 (Japan)

    2002-08-01

    The authors present the case of a newborn girl with extreme fenestration of the basilar artery. This anomaly was found incidentally during MR imaging study for cleft palate and nasopharyngeal teratoma. Magnetic resonance angiography showed a totally duplicated basilar artery with connections at the proximal and distal ends of the artery, suggesting an extreme fenestration. Duplicated pituitary gland was also found on MR imaging. (orig.)

  6. Extreme fenestration of the basilar artery associated with cleft palate, nasopharyngeal mature teratoma, and hypophyseal duplication

    International Nuclear Information System (INIS)

    Uchino, A.; Sawada, A.; Takase, Y.; Kudo, S.; Fujita, I.

    2002-01-01

    The authors present the case of a newborn girl with extreme fenestration of the basilar artery. This anomaly was found incidentally during MR imaging study for cleft palate and nasopharyngeal teratoma. Magnetic resonance angiography showed a totally duplicated basilar artery with connections at the proximal and distal ends of the artery, suggesting an extreme fenestration. Duplicated pituitary gland was also found on MR imaging. (orig.)

  7. Hepatic splenosis mimicking liver metastases in a patient with history of childhood immature teratoma

    OpenAIRE

    Jereb, Sara; Trotovsek, Blaz; Skrbinc, Breda

    2016-01-01

    Abstract Background Hepatic splenosis is rare condition, preceded by splenectomy or spleen trauma, the term refers to nodular implantation of normal splenic tissue in the liver. In patients with history of malignancy in particular, it can be mistaken for metastases and can lead to unnecessary diagnostic procedures or inappropriate treatment. Case report Twenty-two-year old male was treated for immature teratoma linked to undescended right testicle after birth. On regular follow-up examination...

  8. A Retroperitoneal Isolated Enteric Duplication Cyst Mimicking a Teratoma: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Daichi Momosaka

    2016-01-01

    Full Text Available Enteric duplication cysts lacking anatomic association with the gastrointestinal tract are called isolated enteric duplication cysts (IEDCs. We present an atypical case of a retroperitoneal IEDC with a tortuous tubular complex shape that enfolded the surrounding retroperitoneal fat and mimicked a retroperitoneal teratoma. Multiplanar reconstruction images should be used to evaluate such a lesion correctly. A tortuous tubular complex shape could be a key finding to differentiate from other retroperitoneal cysts.

  9. Excision of an intrapericardial immature teratoma in a 26-week premature neonate

    Directory of Open Access Journals (Sweden)

    Robert B. Hawkins

    2016-07-01

    Full Text Available We present a case of a 26-week premature newborn with an immature intrapericardial teratoma. The patient was transferred from an outside hospital for management of a large mediastinal mass causing respiratory insufficiency. The newborn was supported with the help of a large interdisciplinary team until day of life 22 when he underwent surgical excision. On follow up the infant is doing very well and is one of the youngest survivors to date.

  10. Evaluation of Posttransplantation Diabetes Mellitus After Liver Transplantation: Assessment of Insulin Administration as a Risk Factor.

    Science.gov (United States)

    Linder, Kristin E; Baker, William L; Rochon, Caroline; May, Scott T; Sheiner, Patricia A; Martin, Spencer T

    2016-05-01

    Impaired glucose regulation posttransplantation can affect allograft survival and may lead to the development of posttransplant diabetes mellitus (PTDM). The primary purpose of this study is to assess the difference in insulin burden between liver transplant patients who develop PTDM and patients who do not. This was a single-center, retrospective study. Adult liver transplant recipients transplanted between January 1, 2005, and August 1, 2013, were included. PTDM was defined as: (1) use of an oral antihyperglycemic agent for ≥30 consecutive days after transplant, (2) use of insulin ≥30 consecutive days after transplant, or (3) hemoglobin A1C≥6.5 any time after transplant. Of the 114 patients included, 48 (42%) developed PTDM. The average 24-hour insulin requirement on the medical floors was 17.2 ± 14.5 units in the PTDM group and 11.3 ± 12.2 units in the PTDM-free group;P= 0.02. The average blood glucose level on the medical floor was 184.7 ± 31.5 mg/dL in the PTDM group and 169.3 ± 31.4 mg/dL in the PTDM-free group;P= 0.013. Multivariate analysis revealed that experiencing rejection was positively associated with the development of PTDM: adjusted odds ratio (AOR) = 3.237; 95% CI = 1.214-8.633. Basiliximab was negatively associated with the development of PTDM: AOR = 0.182; 95% CI = 0.040-0.836. Univariate analyses suggest that insulin burden is a positive risk factor for the development of PTDM; this association is lost in multivariate analyses. Rejection was a positive predictor, and use of basiliximab was a negative predictor for the development of PTDM. © The Author(s) 2016.

  11. Hepatic splenosis mimicking liver metastases in a patient with history of childhood immature teratoma.

    Science.gov (United States)

    Jereb, Sara; Trotovsek, Blaz; Skrbinc, Breda

    2016-06-01

    Hepatic splenosis is rare condition, preceded by splenectomy or spleen trauma, the term refers to nodular implantation of normal splenic tissue in the liver. In patients with history of malignancy in particular, it can be mistaken for metastases and can lead to unnecessary diagnostic procedures or inappropriate treatment. Twenty-two-year old male was treated for immature teratoma linked to undescended right testicle after birth. On regular follow-up examinations no signs of disease relapse or long-term consequences were observed. He was presented with incidental finding of mature cystic teratoma after elective surgery for what appeared to be left-sided inguinal hernia. The tumour was most likely a metastasis of childhood teratoma. Origin within remaining left testicle was not found. Upon further imaging diagnostics, several intrahepatic lesions were revealed. Based on radiologic appearance they were suspicious to be metastases. The patient underwent two ultrasound guided fine-needle aspiration biopsies. Cytologic diagnosis was inconclusive. Histology of laparoscopically obtained tissue disclosed presence of normal splenic tissue and led to diagnosis of hepatic splenosis. Though hepatic splenosis is rare, it needs to be included in differential diagnosis of nodular hepatic lesions. Accurate interpretation of those lesions is crucial for appropriate management of the patient. If diagnosis eludes after cytologic diagnostics alone, laparoscopic excision of nodular lesion is warranted before considering more extensive liver resection.

  12. Assessing reprogramming by chimera formation and tetraploid complementation.

    Science.gov (United States)

    Li, Xin; Xia, Bao-long; Li, Wei; Zhou, Qi

    2015-01-01

    Pluripotent stem cells can be evaluated by pluripotent markers expression, embryoid body aggregation, teratoma formation, chimera contribution and even more, tetraploid complementation. Whether iPS cells in general are functionally equivalent to normal ESCs is difficult to establish. Here, we present the detailed procedure for chimera formation and tetraploid complementation, the most stringent criterion, to assessing pluripotency.

  13. Conditionally replicating adenovirus prevents pluripotent stem cell–derived teratoma by specifically eliminating undifferentiated cells

    Directory of Open Access Journals (Sweden)

    Kaoru Mitsui

    Full Text Available Incomplete abolition of tumorigenicity creates potential safety concerns in clinical trials of regenerative medicine based on human pluripotent stem cells (hPSCs. Here, we demonstrate that conditionally replicating adenoviruses that specifically target cancers using multiple factors (m-CRAs, originally developed as anticancer drugs, may also be useful as novel antitumorigenic agents in hPSC-based therapy. The survivin promoter was more active in undifferentiated hPSCs than the telomerase reverse transcriptase (TERT promoter, whereas both promoters were minimally active in differentiated normal cells. Accordingly, survivin-responsive m-CRA (Surv.m-CRA killed undifferentiated hPSCs more efficiently than TERT-responsive m-CRAs (Tert.m-CRA; both m-CRAs exhibited efficient viral replication and cytotoxicity in undifferentiated hPSCs, but not in cocultured differentiated normal cells. Pre-infection of hPSCs with Surv.m-CRA or Tert.m-CRA abolished in vivo teratoma formation in a dose-dependent manner following hPSC implantation into mice. Thus, m-CRAs, and in particular Surv.m-CRAs, represent novel antitumorigenic agents that could facilitate safe clinical applications of hPSC-based regenerative medicine.

  14. The ter mutation in the rat Dnd1 gene initiates gonadal teratomas and infertility in both genders.

    Science.gov (United States)

    Northrup, Emily; Zschemisch, Nils-Holger; Eisenblätter, Regina; Glage, Silke; Wedekind, Dirk; Cuppen, Edwin; Dorsch, Martina; Hedrich, Hans-Jürgen

    2012-01-01

    A spontaneous mutation leading to the formation of congenital ovarian and testicular tumors was detected in the WKY/Ztm rat strain. The histological evaluation revealed derivatives from all three germ layers, thereby identifying these tumors as teratomas. Teratocarcinogenesis was accompanied by infertility and the underlying mutation was termed ter. Linkage analysis of 58 (WKY-ter×SPRD-Cu3) F2 rats associated the ter mutation with RNO18 (LOD = 3.25). Sequencing of candidate genes detected a point mutation in exon 4 of the dead-end homolog 1 gene (Dnd1), which introduces a premature stop codon assumed to cause a truncation of the Dnd1 protein. Genotyping of the recessive ter mutation revealed a complete penetrance of teratocarcinogenesis and infertility in homozygous ter rats of both genders. Morphologically non-tumorous testes of homozygous ter males were reduced in both size and weight. This testicular malformation was linked to a lack of spermatogenesis using immunohistochemical and histological staining. Our WKY-Dnd1(ter)/Ztm rat is a novel animal model to investigate gonadal teratocarcinogenesis and the molecular mechanisms involved in germ cell development of both genders.

  15. Isolated Post-Transplantation Lymphoproliferative Disease Involving the Breast and Axilla as Peripheral T-cell Lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ji-Young [Department of Radiology, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul 150-950 (Korea, Republic of); Cha, Eun Suk; Lee, Jee Eun [Department of Radiology, Ewha Womans University School of Medicine, Seoul 158-710 (Korea, Republic of); Sung, Sun Hee [Department of Pathology, Ewha Womans University School of Medicine, Seoul 158-710 (Korea, Republic of)

    2013-07-01

    Post-transplantation lymphoproliferative disorders (PTLDs) are a heterogeneous group of diseases that represent serious complications following immunosuppressive therapy for solid organ or hematopoietic-cell recipients. In contrast to B-cell PTLD, T-cell PTLD is less frequent and is not usually associated with Epstein Barr Virus infection. Moreover, to our knowledge, isolated T-cell PTLD involving the breast is extremely rare and this condition has never been reported previously in the literature. Herein, we report a rare case of isolated T-cell PTLD of the breast that occurred after a patient had been treated for allogeneic peripheral blood stem cell transplantation due to acute myeloblastic leukemia.

  16. Isolated Post-Transplantation Lymphoproliferative Disease Involving the Breast and Axilla as Peripheral T-cell Lymphoma

    International Nuclear Information System (INIS)

    Hwang, Ji-Young; Cha, Eun Suk; Lee, Jee Eun; Sung, Sun Hee

    2013-01-01

    Post-transplantation lymphoproliferative disorders (PTLDs) are a heterogeneous group of diseases that represent serious complications following immunosuppressive therapy for solid organ or hematopoietic-cell recipients. In contrast to B-cell PTLD, T-cell PTLD is less frequent and is not usually associated with Epstein Barr Virus infection. Moreover, to our knowledge, isolated T-cell PTLD involving the breast is extremely rare and this condition has never been reported previously in the literature. Herein, we report a rare case of isolated T-cell PTLD of the breast that occurred after a patient had been treated for allogeneic peripheral blood stem cell transplantation due to acute myeloblastic leukemia

  17. Clinical presentation of epignathus teratoma with cleft palate; and duplication of cranial base, tongue, mandible, and pituitary gland.

    Science.gov (United States)

    Maeda, Yujiro; Suenaga, Hideyuki; Sugiyama, Madoka; Saijo, Hideto; Hoshi, Kazuto; Mori, Yoshiyuki; Takato, Tsuyoshi

    2013-07-01

    A 2-day-old girl was diagnosed with an oral epignathus teratoma and an uncommon combination of orofacial malformations including cleft palate; tongue, mandible, cranial base, cervical vertebrae, lower lip, and pituitary gland duplications; and fistula of the glabella and lower lip. Computed tomography revealed that the mass within the nasal cavity had tooth-like calcifications and protruded into the nasopharynx and oral cavity. It was implanted on the anterior wall of the body of the sphenoid bone and was accompanied with mandibular duplication. Magnetic resonance imaging detected duplication of the pituitary gland and confirmed the absence of intracranial communication of the nasopharyngeal mass. The teratoma did not cause respiratory obstruction; however, the patient required continuous nasogastric tube feeding. Usually, an epignathus teratoma is associated with few midline defects and can be corrected with multiple interventions at different time points. The current study describes the surgical procedure comprising excision of the tumor along with reconstructive surgeries of the mandible, tongue, and fistulae undertaken when the infant reached 7 months of age. The cleft palate was repaired at 18 months of age using the Kaplan buccal flap method. Histopathologic examination confirmed a grade 0 teratoma covered with keratinized skin and containing pilosebaceous and sweat glands, adipose tissue, and smooth muscle. The long-term success of this intervention was determined at the follow-up examination conducted at 3 years of age, with no signs of the teratoma recurrence observed.

  18. Anti-N-methyl-D-aspartate receptor encephalitis associated with an ovarian teratoma: two cases report and anesthesia considerations.

    Science.gov (United States)

    Liu, Haiyang; Jian, Minyu; Liang, Fa; Yue, Hongli; Han, Ruquan

    2015-10-16

    Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an immune-mediated syndrome caused by the production of anti-NMDAR receptor antibodies. The syndrome characterised by psychosis, seizures, sleep disorders, hallucinations and short-term memory loss. Ovarian teratoma is the confirmed tumour associated with anti-NMDAR antibodies. The patients with anti-NMDAR encephalitis complicated by ovarian teratoma require surgical treatment under general anesthesia. NMDARs are important targets of many anesthetic drugs. The perioperative management and complications of anti-NMDAR encephalitis, including hypoventilation, paroxysmal sympathetic hyperactivity (PSH) and epilepsy, are challenging for ansthesiologists. This report described two female patients who presented for resection of the ovarian teratoma, they had confirmed anti-NMDAR encephalitis accompanied by ovarian teratoma. Two patients received gamma globulin treatments and the resection of the ovarian teratoma under total intravenous anesthesia. They were recovered and discharged on the 20(th) and 46(th) postoperative day respectively. There is insufficient evidence about the perioperative management, monitoring and anesthesia management of anti-NMDAR encephalitis. This report was based on the consideration that controversial anesthetics that likely act on NMDARs should be avoided. Additionally, BIS monitoring should to be prudently applied in anti-NMDAR encephalitis because of abnormal electric encephalography (EEG). Anesthesiologists must be careful with regard to central ventilation dysfunctions and PSH due to anti-NMDAR encephalitis.

  19. Massive facial teratoma managed with the ex utero intrapartum treatment (EXIT procedure and use of a 3-dimensional printed model for planning of staged debulking

    Directory of Open Access Journals (Sweden)

    Maggie M. Hodges

    2017-02-01

    Full Text Available Teratomas are the most frequent solid tumor found in neonates. However, only 1.5% of neonatal teratomas originate from facial structures. Neonatal facial teratomas are associated with polyhydramnios, preterm birth, pulmonary hypoplasia, cleft palate, cleft lip, and life-threatening airway compromise. The overall survival reported with these lesions has been between 17 and 87.5%; however survival in the setting of antenatally diagnosed facial teratomas has only been described anecdotally. We present a case of an antenatally diagnosed massive facial teratoma originating from the pterygomaxillary fossa, which was associated with polyhydramnios and pre-term birth. We managed this complex tumor with an ex utero intrapartum treatment (EXIT procedure, multidisciplinary medical and surgical team, and staged excision and reconstruction aided by use of a 3-dimensional printed model. Here we review the surgical management of this rare and complex tumor.

  20. Preventive strategy for hyperkalemia during resection of a large sacrococcygeal teratoma in a neonate

    International Nuclear Information System (INIS)

    Jung, J.W.; Lee, K.H.; Kang, E.S.

    2015-01-01

    A neonate weighed 3.3kg with a huge Sacrococcygeal teratoma extending up to the level of S3, anterior displacement of the anus and rectum underwent operation. He had hyperkalemia caused by massive transfusion and tumor lysis. Regular insulin 0.3 unit and 4ml of normal saline mixture were infused by microinfusion pump at a rate of 3cc/hr with continuous 10% dextrose solution during resection of tumor. During the operation, appropriate potassium concentration was maintained and surgery was completed uneventfully. (author)

  1. Vedolizumab as a Potential Culprit in the Development of Ovarian Teratoma?

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    Judy A. Trieu

    2017-12-01

    Full Text Available Vedolizumab is a new humanized monoclonal antibody that has been reserved for those with moderate-to-severe Crohn’s disease and ulcerative colitis who have failed immunomodulator and TNF-α antagonist therapy, and for those who have an increased risk for developing progressive multifocal leukoencephalopathy. Because it targets gastrointestinal tract-specific lymphocytes, meta-analyses and integrated studies have shown that vedolizumab causes fewer extraintestinal adverse effects, such as opportunistic infections and malignancies, compared with anti-TNF therapies. We present the case of a patient who developed an ovarian teratoma after initiation of vedolizumab therapy.

  2. Hypercalcemia Associated with a Malignant Brenner Tumor Arising from a Mature Cystic Teratoma

    Directory of Open Access Journals (Sweden)

    Michael C. Honigberg

    2012-11-01

    Full Text Available A 60-year-old woman presented with abdominal pain and weight loss and was found to have serum calcium of 15.0 mg/dl. Serum parathyroid hormone-related peptide (PTHrP returned elevated. Imaging suggested bilateral mature cystic teratomas. Her hypercalcemia was treated initially with intravenous saline, as well as intramuscular and subcutaneous calcitonin. She underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy, and final pathology revealed malignant Brenner tumor in association with a mature cystic teratoma. Her postoperative PTHrP returned less than assay, and her total and ionized calcium fell below normal, requiring supplemental calcium and vitamin D. At follow-up one month after discharge, her calcium had normalized. We present the first reported case of hypercalcemia occurring in association with a malignant Brenner tumor. Malignancy-associated hypercalcemia occurs via four principal mechanisms: (1 tumor production of PTHrP; (2 osteolytic bone involvement by primary tumor or metastasis; (3 ectopic activation of vitamin D to 1,25-(OH2 vitamin D, and (4 ectopic production of parathyroid hormone. PTHrP-mediated hypercalcemia is the most common mechanism and was responsible in this case. In patients with paraneoplastic hypercalcemia who undergo surgical treatment, close monitoring and management of serum calcium is necessary both pre- and postoperatively.

  3. Cushing's syndrome in infancy due to ectopic ACTH secretion by a sacro-coccygeal teratoma.

    Science.gov (United States)

    Rydzewska, Marta; Krawczuk-Rybak, Maryna; Zajkowska, Adrianna; Jurczuk, Natalia; Polnik, Dariusz; Szalecki, Mieczysław; Moszczyńska, Elżbieta; Savage, Martin O; Bossowski, Artur

    2017-04-01

    Adenocorticotropic hormone (ACTH)-dependent Cushing's syndrome in infancy is extremely rare. We describe the case of a sacro-coccygeal ectopic ACTH-secreting immature teratoma in an infant who also presented the triad of defects characteristic of Currarino syndrome. A girl was born with a large immature teratoma in the sacro-coccygeal region associated with anal atresia. At the age of 7 days, the concentration of α-fetoprotein (AFP) was above the age-specific normal range. Two non-radical surgical excisions of the tumour were performed. At the age of 7 months, she developed polyphagia, acne, hirsutism, hypertension and hypokalemia with elevated ACTH and absence of serum cortisol circadian rhythm. Immunostaining of tumour tissue showed ACTH-immunoreactive cells. Due to unsuccessful therapy with ketoconazole and resistance to antihypertensive medications [blood pressure (BP) 210/160 mmHg], metyrapone was administered, which controlled her ACTH and cortisol levels in the normal range. Following further removal of tumour bulk after three operations during the first year of life, there was a decrease of BP to normal values. A rare case of ectopic ACTH syndrome causing Cushing's syndrome in infancy in the context of Currarino syndrome is reported. Radical surgery has resulted in excision of the tumour and current control of Cushing's syndrome.

  4. Neoadjuvant Chemotherapy for Facilitating Surgical Resection of Infantile Massive Intracranial Immature Teratoma.

    Science.gov (United States)

    Kitahara, Takahiro; Tsuji, Yoshihito; Shirase, Tomoyuki; Yukawa, Hiroyuki; Takeichi, Yasuhiro; Yamazoe, Naohiro

    2016-04-01

    Immature teratoma (IMT) is the most frequent histological subtype of infantile intracranial teratoma, the most common congenital brain tumor. IMT contains incompletely differentiated components resembling fetal tissues. Infantile intracranial IMT has a dismal prognosis, because it is often inoperable due to its massive size and high vascularity. Neoadjuvant chemotherapy has been shown to be effective in decreasing tumor volume and vascularity to facilitate surgical resection in other types of infantile brain tumors. However, only one recent case report described the effectiveness of neoadjuvant chemotherapy for infantile intracranial IMT in the literature, even though it is common entity with a poor prognosis in infants. Here, we describe the case of a 2-month-old male infant with a very large intracranial IMT. Maximal surgical resection was first attempted but was unsuccessful because of severe intraoperative hemorrhage. Neoadjuvant carboplatin and etoposide (CARE) chemotherapy was then administered with the aim of shrinking and devascularizing the tumor. After neoadjuvant chemotherapy, tumor size did not decrease, but intraoperative blood loss significantly decreased and near-total resection was achieved by the second and third surgery. The patient underwent adjuvant CARE chemotherapy and has been alive for 3 years after surgery without tumor regrowth. Even when neoadjuvant chemotherapy does not decrease tumor volume of infantile intracranial IMT, surgical resection should be tried because chemotherapy can facilitate surgical resection and improve clinical outcome by reducing tumor vascularity.

  5. Paraneoplastic limbic encephalitis in a teenage girl with an immature ovarian teratoma

    International Nuclear Information System (INIS)

    Stein-Wexler, Rebecca; Wootton-Gorges, Sandra L.; Brunberg, James A.; Greco, Claudia M.

    2005-01-01

    Paraneoplastic limbic encephalitis (PLE) is an unusual disorder that is characterized by the association of clinical limbic system abnormalities with neoplasia, usually malignancy. It has rarely been reported in children and then manifests during the teenage years. Diagnosis is often delayed, especially when the tumor has not been recognized. In adults, the diagnosis can be revealed by the presence of antineuronal antibodies. We describe an unusual case of behavioral disturbance leading rapidly to coma in a 14-year-old girl with CSF pleocytosis who was found 10 weeks later to have an immature ovarian teratoma. Although her symptoms eventually improved slightly after tumor excision, she died while in rehabilitation. PLE is an important diagnosis to consider in the teenage girl with symptoms of a progressive limbic disorder and CSF pleocytosis, and whose brain MR imaging demonstrates no abnormality or mild T2-weighted temporal lobe signal abnormality. When this constellation of findings presents in a teenage girl, the possibility of an underlying ovarian teratoma should be considered. (orig.)

  6. Ovarian germ cell tumors with rhabdomyosarcomatous components and later development of growing teratoma syndrome: a case report

    Directory of Open Access Journals (Sweden)

    Al-Jumaily Usama

    2012-01-01

    Full Text Available Abstract Introduction Development of a sarcomatous component in a germ cell tumor is an uncommon phenomenon. Most cases reported have a grim prognosis. Growing teratoma syndrome is also an uncommon phenomenon and occurs in approximately 2% to 7% of non seminomatous germ cell tumors and should be treated surgically. Case presentation We report the case of a 12-year-old Asian girl with an ovarian mixed germ cell tumor containing a rhabdomyosarcomatous component. She was treated with a germ cell tumor chemotherapy regimen and rhabdomyosarcoma-specific chemotherapy. Towards the end of her treatment, she developed a retroperitoneal mass that was increasing in size. It was completely resected, revealing a mature teratoma, consistent with growing teratoma syndrome. She is still in complete remission approximately three years after presentation. Conclusion The presence of rhabdomyosarcoma in a germ cell tumor should be treated by a combined chemotherapy regimen (for germ cell tumor and rhabdomyosarcoma. In addition, development of a mass during or after therapy with normal serum markers should raise the possibility of growing teratoma syndrome that should be treated surgically.

  7. Squamous Cell Carcinoma Arising in Mature Teratoma of the Ovary Masquerading as Abdominal Tuberculosis

    Directory of Open Access Journals (Sweden)

    Shreeya Taresh Indulkar

    2018-01-01

    Full Text Available Pure squamous cell carcinoma (SCC of the ovary is rare. SCC can arise in a mature teratoma (MT, ovarian endometriosis or in a Brenner tumor. SCC is the most common malignant transformation arising in MT and comprises 80% of all cases. Such neoplastic transformations are extremely difficult either to predict or detect early. The mechanism of malignant transformation has not been completely understood. Due to the rarity and the aggressive course, diagnosis and treatment constitute a big challenge. We report a case of SCC arising in MT presenting with a huge abdominopelvic mass and abundant peritoneal collections clinically masquerading as abdominal tuberculosis. A review of literature with special emphasis on prognosis and treatment modalities is also presented.

  8. An observational study on sacrococcygeal teratoma a pediatric tumor at liaquat university hospital, jamshoro, pakistan

    International Nuclear Information System (INIS)

    Goswami, P.; Kella, N.L.; Memon, S.

    2017-01-01

    To high light and add to local literature regarding sacrococcygeal Teratoma (SCT). Methodology: This descriptive study was conducted in the department of Pediatric surgery of Liaquat University Hospital, Sindh, Pakistan from January 2010 to December 2015. A total of 10 patients with SCT were included in the study. Surgery was performed all cases. Data were analyzed using SPSS version 18. Results: Out of 10 patients, 6 were males, 4 were females with age ranging between 20 hours to 08 months. Nine were full term while only one was preterm baby. Four were delivered by normal vaginal delivery and six by cesarean section. Only three were diagnosed by ultrasound in antenatal period while seven in postnatal period. Conclusions: SCT requires surgical excision by team of experts including pediatric surgeon, neonatologist, neurosurgeon and anesthesiologist. Better surgical outcomes are possible in our setup provided surgery in proper time and be properly done. (author)

  9. [Teratoma of the rhinopharynx and the infratemporal fossa in neonates: report of 3 cases].

    Science.gov (United States)

    Benlyazid, A; Lescanne, E; Marque, A; Robier, A; Beutter, P; Ployet, M J

    2001-02-01

    Teratomas are tumors which develop in childhood or early adulthood, generally in the gonads. More rarely these tumors may be found in an axial localization, notably in cervicofacial forms. We report three cases of teratomas observed in rhinopharynx of three neonates operated at the Clocheville General Hospital. We present the main anatomoclinical features of these tumors, focusing on the cervicofacial forms in neonates. All three cases occurred in female neonates presenting acute dyspnea within the first hours of life, requiring intubation in two cases. The first two tumors invaded the infratemoral region and the third was a pediculated tumor of the velum exteriorized via the mouth. In one case antenatal ultrasound had suggested the diagnosis of a right temporomaxillary tumor. Rapid excision of the rhinopharngyeal component allow extubation for the two intubated infants and pathology diagnosis. In the first infant operated at 2 months, the lateral route was adapted to age, with mandibulotomy with section of the coronoid process but preserving the mandibular condyle. The second infant was operated at the age of 3 weeks using a wide frontotemporoperitonial approach then at the age of 3.5 months for recurrence extending to the floor of the temporal fossa and the middle ear. A type C infratemporal approach was used with lost-bone temporal craniectomy. Per-buccal excision was possible in the third infant with resection at the base of implantation. No recurrence has been observed in the first two cases at 3.5 and 2.5 months follow-up in the first two cases. The third infant was lost to follow-up.

  10. A Rare Presentation of the Syndrome of Inappropriate Antidiuretic Hormone in a 12-Year-Old Girl as the Initial Presentation of an Immature Ovarian Teratoma.

    Science.gov (United States)

    Iqbal, Anoop Mohamed; Schwenk, W Frederick

    2018-02-01

    Immature ovarian teratoma is very rare in childhood. We report on a 12-year-old girl with immature ovarian teratoma who presented initially with syndrome of inappropriate antidiuretic hormone. A 12-year-old girl presented with acute abdomen and distention. Initial laboratory tests showed hyponatremia (sodium, 123 mmol/L), that did not respond to fluid management. Computed tomography imaging showed a 15 cm × 9 cm × 20 cm mass in the right ovary with multifocal internal fat, and dystrophic calcifications. She underwent exploratory laparotomy with a right salpingo-oophorectomy, omentectomy, and peritoneal stripping. The pathology revealed metastatic immature teratoma. Hyponatremia resolved soon after the surgery. Although a rare diagnosis, immature ovarian teratoma must be considered in a girl who presents with abdominal mass and hyponatremia. Copyright © 2017 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

  11. Giant posterior fossa mature teratoma with adjacent subacute haematoma, compressive on the brainstem, with acute hydrocephalus. Case report

    Directory of Open Access Journals (Sweden)

    Balasa D.

    2016-09-01

    Full Text Available Mature teratoma of the vermis is a rare entity in neurosurgical adulthood pathology. We present the case of a 65 years old patient, admited as an emergency for intense headache (VAS 8/10, nausea, vomiting, gait ataxia, orizontal nistagmus, dismetria, disdiadocokinezia, predominant on the left side, long tracts signs, predominant on the left side. Native and contrast CT and MRI scan of the head revealed a tumoral lesion, in the vermian, paravermian and in the fourth ventricle, with the aspect of a teratoma with intratumoral subacute haemorrhage including a giant lesion 5,5/5/4,5 cm, compressive on mesencephalon, and with suprajacent acute internal hidrocephalus. Emergency neurosurgery was performed (occipital infratentorial craniectomy, microneurosurgical total tumoral resection and haematoma evacuation. Postoperative, the patient recovered progressivelly , subtotal neo and arhicerebellar symptoms. The motor long tract signs recovered slower and persisted incomplete.

  12. A Metabolomic Approach (1H HRMAS NMR Spectroscopy) Supported by Histology to Study Early Post-transplantation Responses in Islet-transplanted Livers

    OpenAIRE

    Vivot, Kevin; Benahmed, Malika A.; Seyfritz, Elodie; Bietiger, William; Elbayed, Karim; Ruhland, Elisa; Langlois, Allan; Maillard, Elisa; Pinget, Michel; Jeandidier, Nathalie; Gies, Jean-Pierre; Namer, Izzie-Jacques; Sigrist, S?verine; Reix, Nathalie

    2016-01-01

    Intrahepatic transplantation of islets requires a lot of islets because more than 50% of the graft is lost during the 24 hours following transplantation. We analyzed, in a rat model, early post-transplantation inflammation using systemic inflammatory markers, or directly in islet-transplanted livers by immunohistochemistry. 1H HRMAS NMR was employed to investigate metabolic responses associated with the transplantation. Inflammatory markers (Interleukin-6, ?2-macroglobulin) are not suitable t...

  13. Treatment of post-transplantation lymphoproliferative disorders after kidney transplant with rituximab and conversion to m-TOR inhibitor.

    Science.gov (United States)

    Nieto-Rios, John Fredy; Gómez de Los Ríos, Sandra Milena; Serna-Higuita, Lina María; Ocampo-Kohn, Catalina; Aristizabal-Alzate, Arbey; Gálvez-Cárdenas, Kenny Mauricio; Zuluaga-Valencia, Gustavo Adolfo

    2016-12-30

    Post-transplantation lymphoproliferative disorders are serious complications of organ transplantation which treatment is not yet standardized. To describe the clinical response, overall and graft survival of patients in our center with this complication after kidney transplantation, which received rituximab as part of their treatment as well as conversion to m-TOR. Retrospective study, which included patients, diagnosed with post-transplant lymphoproliferative disorders after kidney transplantation from January 2011 to July 2014. Eight cases were found with a wide spectrum of clinical presentations. Most had monomorphic histology, 85% were associated with Epstein-Barr virus, 25% of patients had tumor involvement of the renal graft, and 12.5% ​​had primary central nervous system lymphoma. All patients were managed with reduction of immunosuppression, conversion to m-TOR (except one who lost the graft at diagnosis) and rituximab-based therapy. The overall response rate was 87.5% (62.5% complete response, 25% partial response). Survival was 87.5% with a median follow-up of 34 months. An additional patient lost the graft, with chronic nephropathy already known. All the remaining patients had stable renal function. There are no standardized treatment regimens for lymphoproliferative disorders after kidney transplantation, but these patients can be managed successfully with reduction of immunosuppression, conversion to m-TOR and rituximab-based schemes.

  14. Primary carcinoid tumor arising within mature teratoma of the kidney: report of a rare entity and review of the literature

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    Parwani Anil V

    2007-05-01

    Full Text Available Abstract Background Primary carcinoid tumor arising within mature teratoma of the kidney is extremely rare, and their clinicopathologic features are not well described. Our objective was to further define the clinical features and pathologic spectra of primary carcinoid tumor arising within mature teratoma of the kidney. Methods Six previously reported case reports were identified using MEDLINE and a subsequent bibliographic search of all pertinent reports and reviews was performed. We also searched the electronic medical archival records of our institution and identified one additional unreported case. Data were extracted on the demographics, predisposing factors, clinical presentation, radiographic features, gross pathology, microscopic pathology, immunophenotype, therapy, and outcome of each of these seven cases. Results Primary carcinoid tumor arising within mature teratoma of the kidney was found at a mean age of 41.4 years. Of the 7 cases, 3 were female and 4 were male. Two of the 7 cases (28.6% were associated with horseshoe kidney. It typically presented with abdominal pain without carcinoid syndrome. It typical radiologic appearance was well circumscribed partly calcified Bosniak II-III lesion. Histologically, the carcinoid tumor showed monotonous small round cells arranged in classic anastomosing cords/ribbons intermixed with solid nests. Surgery was curative, no additional treatment was required, no local recurrences occurred, and no metastases occurred in all 7 cases. The 3 cases with available outcome data were alive at the time of publication of their respective cases (mean, 5 months. Conclusion Primary carcinoid tumor arising within mature teratoma of the kidney is a rare tumor that typically presents with abdominal pain without carcinoid syndrome. It is not associated with local recurrence and metastasis, is surgically curable, and has excellent prognosis.

  15. Ependymoma and Carcinoid Tumor Associated with Ovarian Mature Cystic Teratoma in a Patient with Multiple Endocrine Neoplasia I

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    Reed Spaulding

    2014-01-01

    Full Text Available Ovarian teratomas rarely undergo new neoplastic transformation and account for a small percentage of malignant ovarian germ cell neoplasms. Here we report a case of a 51-year-old woman with multiple endocrine neoplasia type I (MEN I who was found to have an ependymoma and neuroendocrine tumor (trabecular carcinoid associated with mature cystic teratoma of her left ovary. The ependymoma component displayed cells with round nuclei and occasional small nucleoli which were focally arranged in perivascular pseudorosettes and true rosettes. Rare mitoses were identified. No necrosis was present. Immunohistochemical staining was positive for S-100 and GFAP. The Ki67 proliferation index was very low (2-3%. In contrast, the endocrine tumor component was composed of small uniform cells with eosinophilic cytoplasm, round nuclei, and speckled chromatin. Immunohistochemical staining was positive for synaptophysin and focally positive for chromogranin. This rare case illustrates that MEN I may have an influence on the pathogenesis of ovarian teratomas as they undergo malignant transformation.

  16. A case of pineal teratoma with intraventricular free fat on CT scan

    International Nuclear Information System (INIS)

    Uede, Teiji; Takaya, Satoru; Shinya, Toshiyuki; Tanabe, Sumiyoshi; Hashi, Kazuo; Sohma, Tsutomu.

    1986-01-01

    Detection of an intraventricular or intratumoral fat-fluid level on the plain craniograms has been known as a characteristic sign indicating the presence of intracranial teratomatous tumors. On CT scans, however, only thirteen cases have been previously reported to be found an intraventricular and/or subarachnoid free fat associated with spontaneous ruptures of these tumors. We reported a case of pineal teratoma with intraventricular free-fat seen on CT scans. A nine-year-old male with precocious puberty was admitted to our hospital complaining a moderate nonpulsatile headache. Neurological examinations were normal without signs of meningeal irritation. The serum and CSF titer of HCG were raised markedly. The laboratory data of the CSF were normal and there were no pathological cells in the CSF. The CT scans revealed a large heterogeneous mass containing multiple areas of negative density in the pineal region. There were negative density droplets in the bilateral frontal horn on the same CT scans indicating a presence of free fats. At surgery, an yellowish oily material was drained from the tumor, but there was no sign of meningitis over the cortical surface of the occipital lobe. An intraventricular free fat on CT scan have been reported in fourteen cases including ours following the first case described by Fawcitt in 1976. Although most of the cases presented headache, only two cases was diagnosed clinically as chemical meningitis. Pathological changes indicating granulomatous meningitis, however, were noted in five cases, all of them presenting seizure attacks. (author)

  17. Hemorrhage is the most common cause of neonatal mortality in patients with sacrococcygeal teratoma.

    Science.gov (United States)

    Kremer, Marijke E B; Wellens, Lianne M; Derikx, Joep P M; van Baren, Robertine; Heij, Hugo A; Wijnen, Marc H W A; Wijnen, René M H; van der Zee, David C; van Heurn, L W Ernest

    2016-11-01

    A small percentage of neonates with sacrococcygeal teratoma die shortly after birth from hemorrhagic complications. The incidence of and risk factors associated with hemorrhagic mortality are unknown. In this multicenter study we determined the incidence of early death in neonates born with SCT and evaluated potential risk factors for hemorrhagic mortality. 235 children with SCT treated from 1970 to 2010 in the Netherlands were retrospectively included. The following candidate risk factors for hemorrhagic mortality were examined: sex, prematurity, Altman type, tumor volume, tumor histology, necessity of emergency operation and time of diagnosis. Eighteen patients (7.7%) died at a median age of 163.5days (range 1.7-973days). Nine patients died of a malignancy. Nine others (3.8%) died postnatally (age 1-27days), six even within two days after birth. In seven of these nine patients death was related to tumor-hemorrhage and/or circulatory failure. Risk factors for hemorrhagic mortality were prematurity, tumor volume>1000cm 3 and performance of an emergency operation. Hemorrhagic mortality of neonates with SCT is relatively high (3.8%) representing almost 70% of the overall mortality in the neonatal period. High-output cardiac failure, internal tumor hemorrhage and perioperative bleeding were the most common causes of early death and were all strongly associated with larger tumor sizes. II (Retrospective study). Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Synchronous primary carcinoid tumor and primary adenocarcinoma arising within mature cystic teratoma of horseshoe kidney: a unique case report and review of the literature

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    Perepletchikov Aleksandr M

    2009-06-01

    Full Text Available Abstract Background Malignant transformation of mature cystic teratoma is a rare complication. While any of the constituent tissues of a teratoma has the potential to undergo malignant transformation, squamous cell carcinoma is the most commonly associated malignancy. Renal carcinoid tumors are rare and frequently associated with horseshoe kidney and renal teratoma. Renal teratoma rarely presents together with carcinoid tumor or adenocarcinoma. To the best of our knowledge, there has never been a report of renal teratoma coexisting with both carcinoid tumor and adenocarcinoma. Methods Here, we present a unique and first case of synchronous primary carcinoid tumor and moderately differentiated adenocarcinoma arising within mature cystic teratoma of horseshoe kidney in a 50-year-old female. Lumbar spine X-ray, done for her complaint of progressive chronic low back pain, accidentally found a large calcification overlying the lower pole of the right kidney. Further radiologic studies revealed horseshoe kidney and a large multiseptated cystic lesion immediately anterior to the right renal pelvis with central calcification and peripheral enhancement. She underwent right partial nephrectomy. Results Macroscopically, the encapsulated complex solid and multiloculated cystic tumor with large calcification, focal thickened walls and filled with yellow-tan gelatinous material. Microscopically, the tumor showed coexistent mature cystic teratoma, moderately differentiated adenocarcinoma and carcinoid tumor. Immunohistochemically, alpha-methylacyl-coenzyme A-racemase, calretinin, CD10 and thyroid transcription factor-1 were negative in all the three components of the tumor. The teratomatous cysts lined by ciliated epithelium showed strong staining for cytokeratin 7 and pancytokeratin, and those lined by colonic-like epithelium showed strong staining for CDX2, cytokeratin 20 and pancytokeratin, but both were negative for calretinin. Additionally, the

  19. Investigation of patients with atypical or severe hyperandrogenaemia including androgen-secreting ovarian teratoma.

    LENUS (Irish Health Repository)

    Dennedy, Michael Conall

    2012-02-01

    Approximately 7% of women of reproductive age manifest polycystic ovary syndrome (PCOS) and <0.5% have other causes of hyperandrogenism including congenital adrenal hyperplasia (CAH), androgen-secreting tumour of an ovary or an adrenal gland, Cushing\\'s syndrome or hyperthecosis. The presence of features atypical of PCOS should prompt more extensive evaluation than that usually undertaken. Features atypical of PCOS include the onset of symptoms outside the decade of 15-25 years, rapid progression of symptoms, the development of virilization and a serum testosterone concentration in excess of twice the upper limit of the reference range. Ethnic background, family history and specific clinical findings, e.g. Cushingoid appearance, may inform a focused investigation. Otherwise, patients should have measurement of 17-hydroxyprogesterone (17-OHP) under basal conditions ideally in the early morning, and if abnormal, they should have measurement of 17-OHP one hour after the administration of synthetic ACTH, 250 microg i.v., to screen for CAH, which is present in approximately 2% of hyperandrogenic patients. The overnight cortisol suppression test employing 1 mg dexamethasone at midnight is a sensitive test for Cushing\\'s syndrome. Coronal tomographic (CT) scanning of the adrenals and transvaginal ultrasonography of the ovaries are the investigations of choice when screening for tumours in these organs. Less frequently required is catheterization and sampling from both adrenal and ovarian veins, which is a technically demanding procedure with potential complications which may provide definitive diagnostic information not available from other investigations. Illustrative case reports highlight some complexities in the investigation of hyperandrogenic patients presenting with features atypical of PCOS and include only the ninth case report of an androgen-secreting ovarian teratoma.

  20. A case of toxic epidermal necrolysis initially affecting the skin site of radiation therapy for an intra-cranial post-transplantation lymphoma

    International Nuclear Information System (INIS)

    Tanoue, Toshihide; Egawa, Kiyofumi; Fukushima, Satoshi; Wakasugi, Syoji; Ono, Tomomichi; Yoshida, Shinsuke; Kouchi, Masato; Nishi, Kazuhiko

    2006-01-01

    We report a case of post-transplantation lymphoma (intra-cranial EBV-related malignant lymphoma) who developed toxic epidermal necrolysis (TEN) during concomitant phenobarbital administration and radiotherapy. The erythema exsudativum multiforme-like eruption first appeared on the site of radiation and extended to approximately 35% of the body surface. After stopping radiation therapy and all medications, including immunosuppressant, anticonvulsant, and diuretic drugs, treatment was successfully administered by systemic corticosteroids including semi-pulse therapy (500 mg of methylpredonisolone sodium succinate for 3 days). (author)

  1. Nutrition in children posttransplantation

    African Journals Online (AJOL)

    status and to detect, prevent and treat late-onset complications such as obesity ... potential, prevent further liver injury, promote liver regeneration, minimise risk of infection and .... Campos ACL, Matias JEF and Coelho JCU. Nutritional Aspects ...

  2. Predicting renal graft failure by sCD30 levels and de novo HLA antibodies at 1year post-transplantation.

    Science.gov (United States)

    Wang, Dong; Wu, Guojun; Chen, Jinhua; Yu, Ziqiang; Wu, Weizhen; Yang, Shunliang; Tan, Jianming

    2012-06-01

    HLA antibodies and sCD30 levels were detected in the serum sampled from 620 renal graft recipients at 1 year post-transplantation, which were followed up for 5 years. Six-year graft and patient survivals were 81.6% and 91.0%. HLA antibodies were detected in 45 recipients (7.3%), of whom there were 14 cases with class I antibodies, 26 cases with class II, and 5 cases with both class I and II. Much more graft loss was record in recipients with HLA antibodies than those without antibodies (60% vs. 15.1%, psCD30 levels were recorded in recipients suffering graft loss than the others (73.9±48.8 U/mL vs. 37.3±14.6 U/mL, psCD30 levels, recipients with low sCD30 levels (sCD30 on graft survival was not only independent but also additive. Therefore, post-transplantation monitoring of HLA antibodies and sCD30 levels is necessary and recipients with elevated sCD30 level and/or de novo HLA antibody should be paid more attention in order to achieve better graft survival. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Histopathological analysis of pre-implantation donor kidney biopsies: association with graft survival and function in one year post-transplantation

    Directory of Open Access Journals (Sweden)

    Karla Lais Pêgas

    2014-04-01

    Full Text Available Introduction: Pre-implantation kidney biopsy is a decision-making tool when considering the use of grafts from deceased donors with expanded criteria, implanting one or two kidneys and comparing this to post-transplantation biopsies. The role of histopathological alterations in kidney compartments as a prognostic factor in graft survival and function has had conflicting results. Objective: This study evaluated the prevalence of chronic alterations in pre-implant biopsies of kidney grafts and the association of findings with graft function and survival in one year post-transplant. Methods: 110 biopsies were analyzed between 2006 and 2009 at Santa Casa de Porto Alegre, including live donors, ideal deceased donors and those with expanded criteria. The score was computed according to criteria suggested by Remuzzi. The glomerular filtration rate (GFR was calculated using the abbreviated MDRD formula. Results: No statistical difference was found in the survival of donors stratified according to Remuzzi criteria. The GFR was significantly associated with the total scores in the groups with mild and moderate alterations, and in the kidney compartments alone, by univariate analysis. The multivariate model found an association with the presence of arteriosclerosis, glomerulosclerosis, acute rejection and delayed graft function. Conclusion: Pre-transplant chronic kidney alterations did not influence the post-transplantation one-year graft survival, but arteriosclerosis and glomerulosclerosis is predictive of a worse GFR. Delayed graft function and acute rejection are independent prognostic factors.

  4. A vocabulary for the identification and delineation of teratoma tissue components in hematoxylin and eosin-stained samples

    Directory of Open Access Journals (Sweden)

    Ramamurthy Bhagavatula

    2014-01-01

    Full Text Available We propose a methodology for the design of features mimicking the visual cues used by pathologists when identifying tissues in hematoxylin and eosin (H&E-stained samples. Background: H&E staining is the gold standard in clinical histology; it is cheap and universally used, producing a vast number of histopathological samples. While pathologists accurately and consistently identify tissues and their pathologies, it is a time-consuming and expensive task, establishing the need for automated algorithms for improved throughput and robustness. Methods: We use an iterative feedback process to design a histopathology vocabulary (HV, a concise set of features that mimic the visual cues used by pathologists, e.g. "cytoplasm color" or "nucleus density." These features are based in histology and understood by both pathologists and engineers. We compare our HV to several generic texture-feature sets in a pixel-level classification algorithm. Results: Results on delineating and identifying tissues in teratoma tumor samples validate our expert knowledge-based approach. Conclusions: The HV can be an effective tool for identifying and delineating teratoma components from images of H&E-stained tissue samples.

  5. A calcific pelvic mass in a woman with chronic spinal pain: a case of mature cystic teratoma.

    Science.gov (United States)

    Kaeser, Martha A; McDonald, Jennifer K; Kettner, Norman W

    2011-12-01

    The purpose of this case is to describe findings of a mature cystic teratoma and to further provide differential diagnoses for ovarian pelvic masses and calcifications. A 27-year-old woman presented to a chiropractic teaching clinic with a chief complaint of chronic multilevel spinal pain. During a full spine radiographic examination, radiopaque densities were incidentally identified in the pelvic bowl visualized through a gonad shield. Follow-up pelvic radiography revealed several radiopacities of uniform density localized in the pelvic bowl. INTERVENTION/OUTCOMES: Medical (gynecological) consultation led to ultrasonography of the pelvis that revealed a mature cystic teratoma. The patient underwent complete excision of the mass through a laparotomy procedure. The patient continued to receive chiropractic treatment of her original cervical and lumbar spine complaints, further suggesting that the pelvic mass was not a source of her musculoskeletal complaints. This case demonstrates the detection and proper referral of a patient with a calcific mass. The presence of a pelvic mass, suspected of arising from the ovary, requires additional diagnostic imaging and careful clinical correlation.

  6. Metastatic mediastinal mature teratoma with malignant transformation in a young man with an adenocarcinoma in a Klinefelter's syndrome: Case report and review of the literature.

    Science.gov (United States)

    Le Fèvre, C; Vigneron, C; Schuster, H; Walter, A; Marcellin, L; Massard, G; Lutz, P; Noël, G

    2018-05-01

    Malignant transformation of mediastinal mature teratoma is extremely rare and worsens the prognosis of the disease. Transformation can appear synchronously to or several years after the initial diagnosis. Clinical and radiological signs can orientate the clinician but the definitive diagnosis is obtained thanks to histology. An 11 year-old boy presented with a mediastinal mature teratoma and bone and pulmonary metastases. He received six cycles of chemotherapy combining etoposide, ifosfamide, cisplatin, followed by resection of a 16×14×9cm mediastinal mass. Karyotype analysis revealed the presence of an additional sex chromosome X (47 XXY) pathognomonic of Klinefelter's syndrome. Ten years later, sciatalgia revealed malignant transformation of a pre-existing sacral bone metastasis into gastrointestinal adenocarcinoma. The patient received four cycles of chemotherapy combining oxaliplatin, 5-fluorouracil and cetuximab. This treatment was followed by a complete resection of the sacral metastasis and completed with adjuvant irradiation of 54Gy in 30 daily fractions. Twelve months after the diagnosis of relapse, the patient remained alive without disease. To our knowledge, this is the first case of adenocarcinoma developed in bone metastases of a mediastinal mature teratoma in a boy with a Klinefelter's syndrome. We propose a review of the literature and an analysis of 20 others published cases of mediastinal teratoma with malignant transformation into adenocarcinoma. Copyright © 2018 Société française de radiothérapie oncologique (SFRO). Published by Elsevier Masson SAS. All rights reserved.

  7. The Postischemic Environment Differentially Impacts Teratoma or Tumor Formation After Transplantation of Human Embryonic Stem Cell-Derived Neural Progenitors

    Czech Academy of Sciences Publication Activity Database

    Seminatore, CH.; Polentes, J.; Ellman, D.; Kozubenko, Nataliya; Itier, V.; Tine, S.; Tritschler, L.; Brenot, M.; Guidou, E.; Blondeau, J.; Lhuillier, M.; Bugi, A.; Aubry, L.; Jendelová, Pavla; Syková, Eva; Perrier, A. L.; Finsen, B.; Onteniente, B.

    2010-01-01

    Roč. 41, č. 1 (2010), s. 153-159 ISSN 0039-2499 Institutional research plan: CEZ:AV0Z50390703 Keywords : brain transplantation * human embryonic stem cells * neural differentiation Subject RIV: FH - Neurology Impact factor: 5.756, year: 2010

  8. Teratoma cervical congênito gigante: relato de caso e revisão quanto às opções terapêuticas Giant congenital cervical teratoma: case report and review about therapeutic options

    Directory of Open Access Journals (Sweden)

    Camila Ferro Miele

    2011-12-01

    Full Text Available OBJETIVO: Relatar um caso de teratoma cervical congênito, destacando a gravidade e as dificuldades terapêuticas associadas. DESCRIÇÃO DO CASO: Mãe de 30 anos, com gestação por fertilização assistida. Com 23 semanas, diagnosticada malformação cervical fetal à direita. Parto cesáreo por indicação fetal com 31 semanas. Recém-nascido masculino, peso ao nascer de 1800g, Apgar 4 e 9, com volumoso processo expansivo à direita, ocupando toda a região cervical, comprometendo a mandíbula e estendendo-se para o terço superior do tórax. Com 40 horas de vida, apresentou insuficiência cardíaca congestiva de alto débito por roubo de fluxo pelo tumor. A partir de 54 horas de vida, houve progressiva deterioração hemodinâmica e respiratória, com hipotensão, anúria e labilidade de oxigenação, refratárias às aminas vasoativas, reposição de volume e aumento do suporte ventilatório. Indicada abordagem cirúrgica para ressecção tumoral, todavia o paciente não apresentou estabilidade clínica que permitisse seu transporte ao centro cirúrgico e faleceu com 70 horas de vida. COMENTÁRIOS: O caso demonstra as dificuldades relacionadas à abordagem pós-natal dos teratomas cervicais volumosos. Apesar do diagnóstico pré-natal, o paciente evoluiu com obstrução de vias aéreas, complicada por um choque cardiogênico refratário, que culminou no óbito. A abordagem intraparto é fundamental nesses pacientes, consistindo em exérese tumoral, enquanto a manutenção da circulação materno-fetal permite a oxigenação fetal contínua. A evolução neonatal no caso descrito é condizente com a literatura que mostra prognóstico reservado quando não é realizada a abordagem cirúrgica intraparto.OBJECTIVE: To report a case of congenital cervical teratoma, highlighting the severity and the therapeutic difficulties associated. CASE DESCRIPTION: A 30-year old mother, with pregnancy by assisted fertilization. At 23 weeks, a cervical fetal

  9. Desordem linfoproliferativa pós-transplante em paciente pediátrico Post-transplantation lymphoproliferative disorder in pediatric patient

    Directory of Open Access Journals (Sweden)

    Paulo Manuel Pêgo Fernandes

    2006-10-01

    Full Text Available Terapias de imunossupressão, a que pacientes transplantados devem ser submetidos, os expõe a um alto risco de desenvolver desordens linfoproliferativas pós-transplante (PTLD. Descrevemos o caso de uma criança submetida a transplante cardíaco aos sete meses de idade e que acabou desenvolvendo PTLD, aos nove anos, diagnosticada por meio de retirada de nódulo pulmonar.Immunosuppressive therapy for transplanted patients exposes them to a high risk of developing posttransplantation lymphoproliferative disorders (PTLD. We report the case of a child undergoing heart transplantation at seven months of age who developed PTLD at nine years of age, diagnosed by resection of a pulmonary nodule.

  10. Congenital cheek teratoma with temporo-mandibular joint ankylosis managed with ultra-thin silicone sheet interpositional arthroplasty.

    Science.gov (United States)

    Bhatnagar, Ankur; Verma, Vinay Kumar; Purohit, Vishal

    2013-01-01

    Primary cheek teratomas are rare with joint ankylosis (TMJA). The fundamental aim in the treatment of TMJA is the successful surgical resection of ankylotic bone, prevention of recurrence, and aesthetic improvement by ensuring functional occlusion. Early treatment is necessary to promote proper growth and function of mandible and to facilitate the positive psychological development of child. Inter-positional arthroplasty with ultra-thin silicone sheet was performed. Advantages include short operative time, less foreign material in the joint space leading to negligible foreign body reactions and least chances of implant extrusion. Instead of excising a large bony segment, a thin silicone sheet was interposed and then sutured ensuring preservation of mandibular height. Aggressive post-operative physiotherapy with custom made dynamic jaw exerciser was used to prevent recurrence.

  11. Malignant Transformation of a Mature Cystic Ovarian Teratoma into Thyroid Carcinoma, Mucinous Adenocarcinoma, and Strumal Carcinoid: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Hilary D. Hinshaw

    2012-01-01

    Full Text Available Malignant transformation of a mature cystic teratoma (MCT is an infrequent, often asymptomatic event. We report the first example of a struma ovarii with a focus of follicular variant of papillary thyroid carcinoma (a, mucinous adenocarcinoma (b, and strumal carcinoid tumor (c—all three arising in one mature cystic teratoma of the ovary. From our reviews, we found limited data to guide management when these malignant foci occur within an MCT. Consideration should be given to thyroidectomy followed by total-body scanning and serum studies for foci of thyroid carcinoma and adjuvant therapy with thyroidectomy and radioablation if residual disease is identified (a. Additionally, extrapolating from data for mucinous adenocarcinomas, consideration could be given to adjuvant chemotherapy after appropriate staging (b. Strumal carcinoid tumors should be treated as tumors of low malignant potential. Observation is appropriate if after complete staging, no invasive implants are noted (c.

  12. Teratoma arising from hepato duodenal ligament in the newborn with transection of portal vein, hepatic artery and common bile duct: A surgical challenge

    Directory of Open Access Journals (Sweden)

    V R Ravikumar

    2018-01-01

    Full Text Available A 7-day-old neonate presented with a large intra-abdominal mass adherent to the hilum of the liver encasing the portal triad. During excision, the portal vein, hepatic artery, and common bile duct were injured. The repair was done promptly and needed massive blood transfusion. Histopathology revealed immature teratoma Grade III. Survival in neonate following total transection of portal triad is rare and has not been reported.

  13. Giant teratoma of anterior mediastinum in a 14-year-old girl as an example of potential diagnostic problems and errors

    Directory of Open Access Journals (Sweden)

    Przemysław Wolak

    2013-10-01

    Full Text Available Teratomas are tumors originating from the three primary germ layers, most commonly located within gonads or in the sacral region. Chest locations are rare. Mediastinal teratoma showing no tumor-specific symptoms may be treated as exudative pneumonia. The goal of the article was to present a case encountered in our practice as a showcase of possible diagnostic problems and errors. Despite a thorough medical examination with additional exams (ultrasound scans of pleural cavities, chest X-ray and laboratory analyses, the diagnosis of a thoracic tumor was made only after chest computed tomography scan was performed following ineffective attempts at antibiotic therapy and pleural drainage. Following the diagnosis of mediastinal tumor, the patient was subjected to surgery. A giant teratoma (confirmed in histopathological examination was removed upon left-sided thoracotomy. Following the procedure, lung expansion and patient recovery were observed. Computed tomography of the chest should be performed routinely upon encountering difficulties in the treatment of exudative pneumonia in children. In every case of pneumonia with pleural effusion in children, inflammatory mask of mediastinal tumors should be ruled out.

  14. Fulminant course in a patient with anti-N-methyl-D-aspartate receptor encephalitis with bilateral ovarian teratomas: A case report and literature review.

    Science.gov (United States)

    Lee, Kuo-Wei; Liou, Li-Min; Wu, Meng-Ni

    2018-04-01

    Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is an autoimmune disorder that can be controlled and reversed by immunotherapy. The presentation of NMDA receptor encephalitis varies, but NMDA receptor encephalitis is seldom reported in patients with both bilateral teratomas and preexisting brain injury. A 28-year-old female with a history of traumatic intracranial hemorrhage presented acute psychosis, seizure, involuntary movement, and conscious disturbance with a fulminant course. Anti-NMDA receptor antibody was identified in both serum and cerebrospinal fluid, confirming the diagnosis of anti-NMDA receptor encephalitis. Bilateral teratomas were also identified during tumor survey. DIAGNOSES:: anti-N-methyl-D-aspartate receptor encephalitis. Tumor resection and immunotherapy were performed early during the course. The patient responded well to tumor resection and immunotherapy. Compared with other reports in the literature, her symptoms rapidly improved without further relapse. This case report demonstrates that bilateral teratomas may be related to high anybody titers and that the preexisting head injury may be responsible for lowering the threshold of neurological deficits. Early diagnosis and therapy are crucial for a good prognosis in such patients.

  15. Acceptance and Use of Mobile Technology for Health Self-Monitoring in Lung Transplant Recipients during the First Year Post-Transplantation.

    Science.gov (United States)

    Jiang, Yun; Sereika, Susan M; Dabbs, Annette DeVito; Handler, Steven M; Schlenk, Elizabeth A

    2016-01-01

    To describe lung transplant recipients (LTRs') acceptance and use of mobile technology for health self-monitoring during the first year post-transplantation, and explore correlates of the use of technology in the 0 to 2, >2 to ≤6, >6 to ≤12, and 0 to 12 months. Secondary analysis of data from 96 LTR assigned to use Pocket PATH(®), a smartphone application, for daily health self-monitoring in a randomized controlled trial. Use of Pocket PATH was categorized as low, moderate, and high use. Proportional odds models for ordinal logistic regression were employed to explore correlates of use of technology. LTR reported high acceptance of Pocket PATH at baseline. However, acceptance was not associated with actual use over the 12 months (p=0.45~0.96). Actual use decreased across time intervals (ptechnology training (p=0.02) in the first 2 months. Higher use from >2 to ≤6 months was associated with greater satisfaction with technology training (OR=3.37, p=0.01) and shorter length of hospital stay (OR=0.98, p=0.02). Higher use from >6 to ≤12 months was associated with older age (OR=1.05, p=0.02), lower psychological distress (OR=0.43, p=0.02), and better physical functioning (OR=1.09, p=0.01). Higher use over 12 months was also associated with older age (OR=1.05, p=0.007), better physical functioning (OR=1.13, p=0.001), and greater satisfaction with technology training (OR=3.05, p=0.02). Correlates were different for short- and long-term use of mobile technology for health self-monitoring in the first year post-transplantation. It is important to follow up with LTR with longer hospital stay, poor physical functioning, and psychological distress, providing ongoing education to improve their long-term use of technology for health self-monitoring.

  16. Age-stratified analysis of tumor markers and tumor characteristics in adolescents and young women with mature cystic teratoma

    Directory of Open Access Journals (Sweden)

    Huseyin Yesilyurt

    2018-06-01

    Full Text Available Background: Serum tumor markers are widely used for the preoperative evaluation of an adnexal mass. Elevations of cancer antigen (CA 125 and CA 19-9 have been reported in patients with mature cystic teratoma (MCT. The aim of the study is to investigate the relation of serum tumor markers with tumor characteristics in young women with MCT. Methods: We conducted a retrospective review of 157 patients under the age of 35 who underwent laparoscopic surgery for ovarian MCT. Patients were divided into two age groups: Group I (n = 80: adolescents/young adults (aged 13–25 years and Group II (n = 77: women aged 26–35 years. Data were analyzed for serum tumor markers, tumor size, and bilaterality. Results: The rates of elevated CA 125 and CA 19-9 were 10.7% and 31.5%, respectively, for Group I, and 13.9% and 26.5%, respectively, for Group II. The bilaterality rate was higher in Group II compared to Group I (19.5% vs. 8.8%, respectively, p = 0.04. Serum CA 125 and CA 19-9 elevations were not related to tumor size in Group I. In Group II, elevated levels of CA 125 were also unrelated to tumor size. However, significant elevation in CA 19-9 levels was observed when tumor size was larger than 4 cm in this age group (p = 0.004. Elevated CA 125 and CA 19-9 levels were not significantly associated with the presence of bilateral MCT in either group. Conclusion: The results of our study indicate that elevations of CA 19-9 are associated with larger tumor size in women aged 26–35 years, but not in adolescents/young adults. However, elevated serum CA 125 levels are not related to tumor size in either age group. Keywords: Adolescents, Mature cystic teratoma, Tumor marker, Tumor size, Young women

  17. A Metabolomic Approach (1H HRMAS NMR Spectroscopy) Supported by Histology to Study Early Post-transplantation Responses in Islet-transplanted Livers.

    Science.gov (United States)

    Vivot, Kevin; Benahmed, Malika A; Seyfritz, Elodie; Bietiger, William; Elbayed, Karim; Ruhland, Elisa; Langlois, Allan; Maillard, Elisa; Pinget, Michel; Jeandidier, Nathalie; Gies, Jean-Pierre; Namer, Izzie-Jacques; Sigrist, Séverine; Reix, Nathalie

    2016-01-01

    Intrahepatic transplantation of islets requires a lot of islets because more than 50% of the graft is lost during the 24 hours following transplantation. We analyzed, in a rat model, early post-transplantation inflammation using systemic inflammatory markers, or directly in islet-transplanted livers by immunohistochemistry. 1 H HRMAS NMR was employed to investigate metabolic responses associated with the transplantation. Inflammatory markers (Interleukin-6, α2-macroglobulin) are not suitable to follow islet reactions as they are not islet specific. To study islet specific inflammatory events, immunohistochemistry was performed on sections of islet transplanted livers for thrombin (indicator of the instant blood-mediated inflammatory reaction (IBMIR)) and granulocytes and macrophages. We observed a specific correlation between IBMIR and granulocyte and macrophage infiltration after 12 h. In parallel, we identified a metabolic response associated with transplantation: after 12 h, glucose, alanine, aspartate, glutamate and glutathione were significantly increased. An increase of glucose is a marker of tissue degradation, and could be explained by immune cell infiltration. Alanine, aspartate and glutamate are inter-connected in a common metabolic pathway known to be activated during hypoxia. An increase of glutathione revealed the presence of antioxidant protection. In this study, IBMIR visualization combined with 1 H HRMAS NMR facilitated the characterization of cellular and molecular pathways recruited following islet transplantation.

  18. A Metabolomic Approach (1H HRMAS NMR Spectroscopy) Supported by Histology to Study Early Post-transplantation Responses in Islet-transplanted Livers

    Science.gov (United States)

    Vivot, Kevin; Benahmed, Malika A.; Seyfritz, Elodie; Bietiger, William; Elbayed, Karim; Ruhland, Elisa; Langlois, Allan; Maillard, Elisa; Pinget, Michel; Jeandidier, Nathalie; Gies, Jean-Pierre; Namer, Izzie-Jacques; Sigrist, Séverine; Reix, Nathalie

    2016-01-01

    Intrahepatic transplantation of islets requires a lot of islets because more than 50% of the graft is lost during the 24 hours following transplantation. We analyzed, in a rat model, early post-transplantation inflammation using systemic inflammatory markers, or directly in islet-transplanted livers by immunohistochemistry. 1H HRMAS NMR was employed to investigate metabolic responses associated with the transplantation. Inflammatory markers (Interleukin-6, α2-macroglobulin) are not suitable to follow islet reactions as they are not islet specific. To study islet specific inflammatory events, immunohistochemistry was performed on sections of islet transplanted livers for thrombin (indicator of the instant blood-mediated inflammatory reaction (IBMIR)) and granulocytes and macrophages. We observed a specific correlation between IBMIR and granulocyte and macrophage infiltration after 12 h. In parallel, we identified a metabolic response associated with transplantation: after 12 h, glucose, alanine, aspartate, glutamate and glutathione were significantly increased. An increase of glucose is a marker of tissue degradation, and could be explained by immune cell infiltration. Alanine, aspartate and glutamate are inter-connected in a common metabolic pathway known to be activated during hypoxia. An increase of glutathione revealed the presence of antioxidant protection. In this study, IBMIR visualization combined with 1H HRMAS NMR facilitated the characterization of cellular and molecular pathways recruited following islet transplantation. PMID:27766032

  19. A huge ovarian mucinous cystadenoma associated with contralateral teratoma and polycystic ovary syndrome in an obese adolescent girl.

    Science.gov (United States)

    Thaweekul, Patcharapa; Thaweekul, Yuthadej; Mairiang, Karicha

    2016-12-01

    A 13-year-old, obese girl presented with acute abdominal pain with abdominal distension for a year. The physical examination revealed marked abdominal distension with a large well-circumscribed mass sized 13×20 cm. Her body mass index (BMI) was 37.8 kg/m2. An abdominal CT scan revealed a huge multiloculated cystic mass and a left adnexal mass. She had an abnormal fasting plasma glucose and low HDL-C. Laparotomy, right salpingooophorectomy, left cystectomy, lymph node biopsies and partial omentectomy were performed. The left ovary demonstrated multiple cystic follicles over the cortex. The histologic diagnosis was a mucinous cystadenoma of the right ovary and a matured cystic teratoma of the left ovary. Both obesity and polycystic ovary syndrome (PCOS) are associated with a greater risk of ovarian tumours, where PCOS could be either the cause or as a consequence of an ovarian tumour. We report an obese, perimenarchal girl with bilateral ovarian tumours coexistent with a polycystic ovary and the metabolic syndrome.

  20. Abnormal umbilical cord Doppler sonograms may predict impending demise in fetuses with sacrococcygeal teratoma. A report of two cases.

    Science.gov (United States)

    Olutoye, Oluyinka O; Johnson, Mark P; Coleman, Beverly G; Crombleholme, Timothy M; Adzick, N Scott; Flake, Alan W

    2004-01-01

    To identify factors predictive of fetal demise in fetuses with sacrococcygeal teratoma (SCT). The recent management of monochorionic twins discordant for a large SCT and a singleton with a large SCT was reviewed. Serial fetal echocardiography and ultrasonography with Doppler flow measurements documented rapid growth of the SCT in both cases with a relatively modest increase in combined cardiac output. No placentomegaly or hydrops was observed at any time. In both fetuses with SCT, evolution of abnormal umbilical artery waveforms was observed with the ultimate development of reversed end-diastolic umbilical arterial flow that was followed by sudden fetal demise. Death in these 2 fetuses with large SCTs in the absence of placentomegaly/hydrops or hemodynamic changes suggestive of evolving high-output failure suggests a previously unrecognized mechanism of death in fetuses with large rapidly growing SCTs. In these cases, fetal demise may only be heralded by abnormal umbilical artery waveforms that progress to the premorbid observation of reversed diastolic umbilical artery blood flow. Umbilical artery waveform analysis should be closely monitored with other hemodynamic parameters in fetuses with large SCTs. In such fetuses, depending on the gestational age, abnormalities in umbilical artery waveform should be considered indications for early delivery or in utero intervention to prevent fetal demise. Copyright 2004 S. Karger AG, Basel

  1. Abnormal umbilical cord Dopplers may predict impending demise in fetuses with sacrococcygeal teratoma. A report of 2 cases.

    Science.gov (United States)

    Olutoye, Oluyinka O; Johnson, Mark P; Coleman, Beverly G; Crombleholme, Timothy M; Adzick, N Scott; Flake, Alan W

    2003-01-01

    To identify factors predictive of fetal demise in fetuses with sacrococcygeal teratoma (SCT). The recent management of monochorionic twins discordant for a large SCT and a singleton with a large SCT were reviewed. Serial fetal echocardiography and ultrasonography with Doppler flow measurements documented rapid growth of the SCT in both cases with a relatively modest increase in combined cardiac output. No placentomegaly or hydrops was observed at any time. In both fetuses with SCT, evolution of abnormal umbilical artery waveforms was observed with the ultimate development of reversed end-diastolic umbilical arterial flow that was followed by sudden fetal demise. Death in these 2 fetuses with large SCTs in the absence of placentomegaly/hydrops or hemodynamic changes suggestive of evolving high-output failure suggests a previously unrecognized mechanism of death in fetuses with large rapidly growing SCTs. In these cases, fetal demise may only be heralded by abnormal umbilical artery waveforms that progress to the premorbid observation of reversed diastolic umbilical artery blood flow. Umbilical artery waveform analysis should be closely monitored with other hemodynamic parameters in fetuses with large SCTs. In such fetuses, depending on the gestational age, abnormalities in umbilical artery waveform should be considered indications for early delivery or in utero intervention to prevent fetal demise. Copyright 2003 S. Karger AG, Basel

  2. T cell costimulation blockade promotes transplantation tolerance in combination with sirolimus and post-transplantation cyclophosphamide for haploidentical transplantation in children with severe aplastic anemia.

    Science.gov (United States)

    Jaiswal, Sarita Rani; Bhakuni, Prakash; Zaman, Shamsuz; Bansal, Satish; Bharadwaj, Priyanka; Bhargava, Sneh; Chakrabarti, Suparno

    2017-08-01

    We conducted a pilot study employing extended T cell costimulation blockade (COSBL) with Abatacept along with sirolimus and post-transplantation cyclophosphamide (PTCy) in 10 patients (median age 12) with severe aplastic anemia (SAA). Nine patients engrafted in the COSBL group, compared to all 10 patients (median 14 vs 13days) treated on PTCy protocols without abatacept (CONTROL group). The incidence of acute graft-versus-host disease (GVHD) was 10.5% in the COSBL group compared to 50% in the CONTROL group (p=0.04). Chronic GVHD (12.5% vs 56%, p=0.02) and CMV reactivation (30% vs 80%, p=0.03) were also reduced in the COSBL group. T and NK cell subset analysis revealed higher CD56 bright CD16 - NK cells in the CONTROL group (p=0.004), but similar CD56 dim CD16 + NK cells in both groups at day+30. Tregs (CD4 + CD25 + CD127 dim/- FoxP3+) were markedly higher in the COSBL group at day+30 (8.4% vs 1.1%) and the trend was maintained through day+90 (p<0.01). The GVHD and Disease-free survival at one year in the COSBL group was 80% vs. 30% in the CONTROL group (p=0.05). Our preliminary findings suggest that COSBL in combination with PTCy and sirolimus might augment transplantation tolerance in children with SAA, probably due to synergistic effect on early recovery of Tregs. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Utility of 99mTc-MAG3 perfusion indices in the evaluation of renal transplant function during early post-transplantation period

    International Nuclear Information System (INIS)

    Kim, Sung Hoon; Chung, Soo Kyo

    2000-01-01

    We have examined the utility of 99m Tc-MAG3 perfusion indices for assessing renal graft function in early post-transplantation period. Our study included 80 renal transplant recipients (48 men and 32 women, mean age:40.3 years). Diagnosis was based on biopsy, laboratory data and clinical course. Renal scintigraphy (RS) was obtained using 100 MBq of 99m Tc-MAG3 from 11 days to 23 days of kidney transplantation. We measured 5 indices in whole-kidney (WK) and cortical (C) renograms; Hilson's perfusion index (PI), transplant perfusion index (TP) and transplant function index (TF) as perfusion parameter, and the time to peak activity (Tmax) and the ratio of renal counts at 20 min to that at 3 min (K20/3) as functional parameter. The diagnoses at the day of RS were normal graft (NG) in 44, acute rejection (AR) in 14, acute tubular necrosis (ATN) in 10, and Cyclosporine A nephrotoxicity (CsA) in 12. TP and TF were significantly decreased in AR, ATN and CsA, compared to those in NG. K20/3 of AR and ATN were significantly greater than that of NG. WK-Tmax of AR was significantly longer than than that of NG. K20.3 of AR and C-K20/3 of ATN were significantly prolonged relative to those of CsA. There were no statistically significant perfusion indices among complication groups. TP and TF reflecting microperfusion and initial tubular extraction are reliable in assessing graft function. However, it is required to correlate perfusion indices with functional indices and clinical course in differentiating from one another among complication groups

  4. Utility of {sup 99m}Tc-MAG3 perfusion indices in the evaluation of renal transplant function during early post-transplantation period

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Hoon; Chung, Soo Kyo [College of Medicine, The Catholic Univ. of Korea, Seoul (Korea, Republic of)

    2000-12-01

    We have examined the utility of {sup 99m}Tc-MAG3 perfusion indices for assessing renal graft function in early post-transplantation period. Our study included 80 renal transplant recipients (48 men and 32 women, mean age:40.3 years). Diagnosis was based on biopsy, laboratory data and clinical course. Renal scintigraphy (RS) was obtained using 100 MBq of {sup 99m}Tc-MAG3 from 11 days to 23 days of kidney transplantation. We measured 5 indices in whole-kidney (WK) and cortical (C) renograms; Hilson's perfusion index (PI), transplant perfusion index (TP) and transplant function index (TF) as perfusion parameter, and the time to peak activity (Tmax) and the ratio of renal counts at 20 min to that at 3 min (K20/3) as functional parameter. The diagnoses at the day of RS were normal graft (NG) in 44, acute rejection (AR) in 14, acute tubular necrosis (ATN) in 10, and Cyclosporine A nephrotoxicity (CsA) in 12. TP and TF were significantly decreased in AR, ATN and CsA, compared to those in NG. K20/3 of AR and ATN were significantly greater than that of NG. WK-Tmax of AR was significantly longer than than that of NG. K20.3 of AR and C-K20/3 of ATN were significantly prolonged relative to those of CsA. There were no statistically significant perfusion indices among complication groups. TP and TF reflecting microperfusion and initial tubular extraction are reliable in assessing graft function. However, it is required to correlate perfusion indices with functional indices and clinical course in differentiating from one another among complication groups.

  5. Non-germ cell tumours arising in germ cell tumours (teratoma with malignant transformation) in men: CT and MR findings

    Energy Technology Data Exchange (ETDEWEB)

    Athanasiou, A. [Department of Radiology, Institut Gustave-Roussy, Villejuif (France); Department of Radiology, Institut Curie, Paris (France)], E-mail: alexandra.athanasiou@curie.net; Vanel, D. [Department of Radiology, Institut Gustave-Roussy, Villejuif (France); Department of Radiology, Istituti Ortopedici Rizzoli, Bologna (Italy); El Mesbahi, O. [Department of Medicine, Institut Gustave-Roussy, Villejuif (France); Theodore, C. [Department of Medicine, Institut Gustave-Roussy, Villejuif (France); Department of Oncology, Hopital Foch, Suresnes (France); Fizazi, K. [Department of Medicine, Institut Gustave-Roussy, Villejuif (France)

    2009-02-15

    Purpose: To describe the imaging findings of germ cell tumours (GCT) containing non-germ cell malignant components (also designated teratoma with malignant transformation or TMT). Patients and methods: The records of 14 male patients with GCT and a non-germ cell histological component TMT were retrospectively reviewed. All patients had computed tomography (CT) and/or magnetic resonance (MR) studies before and after initial surgery and chemotherapy, as well as during follow-up. Imaging findings were correlated with the response to treatment and with overall survival. Pathological evaluation, immunohistochemistry, serum alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) were also taken into consideration. Sarcoma was identified in 10 out of 14 patients, with rhabdomyosarcoma ranking first (n = 4), followed by osteosarcoma (n = 2), fusiform cell sarcoma (n = 1), undifferentiated sarcoma (n = 1), neurosarcoma (n = 1) and myxoid sarcoma (n = 1). Other histological types of malignant transformation included adenocarcinoma (n = 3) and bronchoalveolar carcinoma (n = 1). Overall, 9 patients relapsed at a median time of 84 months (range 60-168). Results: Non-GCT malignant transformation was identified in the retroperitoneum (5), testis (3), mediastinum (3), peritoneum (2) and lungs (1). The CT and MR imaging findings before treatment and after relapse were evaluated with emphasis on imaging features that could possibly imply the presence of malignant transformation (heterogeneously enhancing soft-tissue masses, ossified masses with calcified lymph nodes, diffuse epiploic thickening associated with ascites and peritoneal nodules, pulmonary alveolar infiltration with septal thickening). All but 1 patient with TMT presented with nodal and distant metastases. The prognosis was poor: within a median follow-up of 59 months (range 3-180), 4 out of 14 patients were alive. Conclusion: TMT is rare and associated with poorer survival compared to GCT. Imaging can be useful

  6. Collagen-IV supported embryoid bodies formation and differentiation from buffalo (Bubalus bubalis) embryonic stem cells

    International Nuclear Information System (INIS)

    Taru Sharma, G.; Dubey, Pawan K.; Verma, Om Prakash; Pratheesh, M.D.; Nath, Amar; Sai Kumar, G.

    2012-01-01

    Graphical abstract: EBs formation, characterization and expression of germinal layers marker genes of in vivo developed teratoma using four different types of extracellular matrices. Highlights: ► Collagen-IV matrix is found cytocompatible for EBs formation and differentiation. ► Established 3D microenvironment for ES cells development and differentiation into three germ layers. ► Collagen-IV may be useful as promising candidate for ES cells based therapeutic applications. -- Abstract: Embryoid bodies (EBs) are used as in vitro model to study early extraembryonic tissue formation and differentiation. In this study, a novel method using three dimensional extracellular matrices for in vitro generation of EBs from buffalo embryonic stem (ES) cells and its differentiation potential by teratoma formation was successfully established. In vitro derived inner cell masses (ICMs) of hatched buffalo blastocyst were cultured on buffalo fetal fibroblast feeder layer for primary cell colony formation. For generation of EBs, pluripotent ES cells were seeded onto four different types of extracellular matrices viz; collagen-IV, laminin, fibronectin and matrigel using undifferentiating ES cell culture medium. After 5 days of culture, ESCs gradually grew into aggregates and formed simple EBs having circular structures. Twenty-six days later, they formed cystic EBs over collagen matrix with higher EBs formation and greater proliferation rate as compared to other extracellular matrices. Studies involving histological observations, fluorescence microscopy and RT-PCR analysis of the in vivo developed teratoma revealed that presence of all the three germ layer derivatives viz. ectoderm (NCAM), mesoderm (Flk-1) and endoderm (AFP). In conclusion, the method described here demonstrates a simple and cost-effective way of generating EBs from buffalo ES cells. Collagen-IV matrix was found cytocompatible as it supported buffalo EBs formation, their subsequent differentiation could prove to

  7. Collagen-IV supported embryoid bodies formation and differentiation from buffalo (Bubalus bubalis) embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Taru Sharma, G., E-mail: gts553@gmail.com [Reproductive Physiology Laboratory, Division of Physiology and Climatology, Indian Veterinary Research Institute, Izatnagar-243 122, Bareilly, U.P. (India); Dubey, Pawan K.; Verma, Om Prakash; Pratheesh, M.D.; Nath, Amar; Sai Kumar, G. [Reproductive Physiology Laboratory, Division of Physiology and Climatology, Indian Veterinary Research Institute, Izatnagar-243 122, Bareilly, U.P. (India)

    2012-08-03

    Graphical abstract: EBs formation, characterization and expression of germinal layers marker genes of in vivo developed teratoma using four different types of extracellular matrices. Highlights: Black-Right-Pointing-Pointer Collagen-IV matrix is found cytocompatible for EBs formation and differentiation. Black-Right-Pointing-Pointer Established 3D microenvironment for ES cells development and differentiation into three germ layers. Black-Right-Pointing-Pointer Collagen-IV may be useful as promising candidate for ES cells based therapeutic applications. -- Abstract: Embryoid bodies (EBs) are used as in vitro model to study early extraembryonic tissue formation and differentiation. In this study, a novel method using three dimensional extracellular matrices for in vitro generation of EBs from buffalo embryonic stem (ES) cells and its differentiation potential by teratoma formation was successfully established. In vitro derived inner cell masses (ICMs) of hatched buffalo blastocyst were cultured on buffalo fetal fibroblast feeder layer for primary cell colony formation. For generation of EBs, pluripotent ES cells were seeded onto four different types of extracellular matrices viz; collagen-IV, laminin, fibronectin and matrigel using undifferentiating ES cell culture medium. After 5 days of culture, ESCs gradually grew into aggregates and formed simple EBs having circular structures. Twenty-six days later, they formed cystic EBs over collagen matrix with higher EBs formation and greater proliferation rate as compared to other extracellular matrices. Studies involving histological observations, fluorescence microscopy and RT-PCR analysis of the in vivo developed teratoma revealed that presence of all the three germ layer derivatives viz. ectoderm (NCAM), mesoderm (Flk-1) and endoderm (AFP). In conclusion, the method described here demonstrates a simple and cost-effective way of generating EBs from buffalo ES cells. Collagen-IV matrix was found cytocompatible as it

  8. Rare extragonadal teratomas in children: complete tumor excision as a reliable and essential procedure for significant survival. Clinical experience and review of the literature.

    Science.gov (United States)

    Paradies, Guglielmo; Zullino, Francesca; Orofino, Antonio; Leggio, Samuele

    2014-01-01

    Extragonadal teratomas are rare tumors in neonates and infants and can sometimes show unusual, distinctive feature such as an unusual location, a clinical sometimes acute, presentation and a "fetiform" histotype of the lesion. We have extrapolated, from our entire experience of teratomas, 4 unusual cases, mostly operated as emergencies; 2 of them were treated just after birth. Aim of this paper is to report the clinical and pathological findings, to evaluate the surgical approach and the long-term biological behaviour in these cases, in the light of survival and current insights reported in the literature. The Authors reviewed the most significant (Tables I and II) clinical, laboratory, radiologic, and pathologic findings, surgical procedures, early and long-term results in 4 children, 1 male and 3 females (M/F ratio: 1/3), suffering from extragonadal teratomas, located in the temporo-zygomatic region of the head (Case n. 1, Fig. 1), retroperitoneal space (Case n. 2, Fig. 2) ,liver (Case n. 3, Figg. 3-5), kidney (Case n. 4, Fig. 6, 7), respectively. Of the 4 patients, 2 were treated neonatally (1 T. of the head, 1 retroperitoneal T.) A prenatal diagnosis had already been made in 2 of the 4 patients, between the 2nd and 3rd trimester of pregnancy, All the infants were born by scheduled caesarean section in a tertiary care hospital and were the immediately referred to thew N.I.C.Us. Because of a mostly acute clinical presentation, the 4 patients were then referred to the surgical unit at different ages: 7 days, 28 days, 7 months, and 4 years respectively. The initial clinical presentation (Table II) was consistent with the site of the mass and/or its side effects. The 2 newborns (Case 1 and 2) both with a prenatally diagnosed mass located at the temporozygomatic region and in the abdominal cavite respectively, already displayed, at birth a mass with a tendency to further growth. The symptoms and signs described to the primary care physician by the parents of the 2

  9. The presence of centrioles and centrosomes in ovarian mature cystic teratoma cells suggests human parthenotes developed in vitro can differentiate into mature cells without a sperm centriole

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Bo Yon, E-mail: boyonlee@gmail.com [Department of Obstetrics and Gynecology, Kyung Hee University Hospital, Kyung Hee University, School of Medicine, Seoul (Korea, Republic of); Shim, Sang Woo; Kim, Young Sun; Kim, Seung Bo [Department of Obstetrics and Gynecology, Kyung Hee University Hospital, Kyung Hee University, School of Medicine, Seoul (Korea, Republic of)

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer The sperm centriole is the progenitor of centrosomes in all somatic cells. Black-Right-Pointing-Pointer Centrioles and centrosomes exist in parthenogenetic ovarian teratoma cells. Black-Right-Pointing-Pointer Without a sperm centriole, parthenogenetic oocytes produce centrioles and centrosomes. Black-Right-Pointing-Pointer Parthenogenetic human oocytes can develop and differentiate into mature cells. -- Abstract: In most animals, somatic cell centrosomes are inherited from the centriole of the fertilizing spermatozoa. The oocyte centriole degenerates during oogenesis, and completely disappears in metaphase II. Therefore, the embryos generated by in vitro parthenogenesis are supposed to develop without any centrioles. Exceptional acentriolar and/or acentrosomal developments are possible in mice and in some experimental cells; however, in most animals, the full developmental potential of parthenogenetic cells in vitro and the fate of their centrioles/centrosomes are not clearly understood. To predict the future of in vitro human parthenogenesis, we explored the centrioles/centrosomes in ovarian mature cystic teratoma cells by immunofluorescent staining and transmission electron microscopy. We confirmed the presence of centrioles and centrosomes in these well-known parthenogenetic ovarian tumor cells. Our findings clearly demonstrate that, even without a sperm centriole, parthenotes that develop from activated oocytes can produce their own centrioles/centrosomes, and can even develop into the well-differentiated mature tissue.

  10. The presence of centrioles and centrosomes in ovarian mature cystic teratoma cells suggests human parthenotes developed in vitro can differentiate into mature cells without a sperm centriole

    International Nuclear Information System (INIS)

    Lee, Bo Yon; Shim, Sang Woo; Kim, Young Sun; Kim, Seung Bo

    2011-01-01

    Highlights: ► The sperm centriole is the progenitor of centrosomes in all somatic cells. ► Centrioles and centrosomes exist in parthenogenetic ovarian teratoma cells. ► Without a sperm centriole, parthenogenetic oocytes produce centrioles and centrosomes. ► Parthenogenetic human oocytes can develop and differentiate into mature cells. -- Abstract: In most animals, somatic cell centrosomes are inherited from the centriole of the fertilizing spermatozoa. The oocyte centriole degenerates during oogenesis, and completely disappears in metaphase II. Therefore, the embryos generated by in vitro parthenogenesis are supposed to develop without any centrioles. Exceptional acentriolar and/or acentrosomal developments are possible in mice and in some experimental cells; however, in most animals, the full developmental potential of parthenogenetic cells in vitro and the fate of their centrioles/centrosomes are not clearly understood. To predict the future of in vitro human parthenogenesis, we explored the centrioles/centrosomes in ovarian mature cystic teratoma cells by immunofluorescent staining and transmission electron microscopy. We confirmed the presence of centrioles and centrosomes in these well-known parthenogenetic ovarian tumor cells. Our findings clearly demonstrate that, even without a sperm centriole, parthenotes that develop from activated oocytes can produce their own centrioles/centrosomes, and can even develop into the well-differentiated mature tissue.

  11. {alpha}{sub v}{beta}{sub 3} imaging can accurately distinguish between mature teratoma and necrosis in {sup 18}F-FDG-negative residual masses after treatment of non-seminomatous testicular cancer: a preclinical study

    Energy Technology Data Exchange (ETDEWEB)

    Aide, Nicolas [Francois Baclesse Cancer Centre and Caen University, Bioticla Team, EA1772, IFR 146 ICORE, GRECAN, Caen (France); Caen University Hospital and Francois Baclesse Cancer Centre, PET Unit, Caen (France); Centre Francois Baclesse, Service de Medecine Nucleaire, Caen (France); Briand, Melanie; Dutoit, Soizic; Deslandes, Edwiges; Poulain, Laurent [Francois Baclesse Cancer Centre and Caen University, Bioticla Team, EA1772, IFR 146 ICORE, GRECAN, Caen (France); Bohn, Pierre; Rouvet, Jean; Modzelewski, Romain; Vera, Pierre [Henri Becquerel Cancer Center and Rouen University Hospital and QuantIF- LITIS (EA4108), Department of Nuclear Medicine, Rouen (France); Lasnon, Charline [Caen University Hospital and Francois Baclesse Cancer Centre, PET Unit, Caen (France); Chasle, Jacques [Francois Baclesse Cancer Centre and Caen University, Pathology Department, Caen (France); Vela, Antony [Francois Baclesse Cancer Centre and Caen University, Radiophysics Unit, Caen (France); Carreiras, Franck [Universite de Cergy Pontoise, UFR Sciences et Techniques, ERRMECe, EA 1391, Institut des materiaux, Cergy-Pontoise (France)

    2011-02-15

    We assessed whether imaging {alpha}{sub v}{beta}{sub 3} integrin could distinguish mature teratoma from necrosis in human non-seminomatous germ cell tumour (NSGCT) post-chemotherapy residual masses. Human embryonal carcinoma xenografts (six/rat) were untreated (controls) or treated to form mature teratomas with low-dose cisplatin and all-trans retinoic acid (ATRA) over a period of 8 weeks. In another group, necrosis was induced in xenografts with high-dose cisplatin plus etoposide (two cycles).{sup 18}F-Fluorodeoxyglucose ({sup 18}F-FDG) small animal positron emission tomography (SA PET) imaging was performed in three rats (one control and two treated for 4 and 8 weeks with cisplatin+ATRA). Imaging of {alpha}{sub v}{beta}{sub 3} expression was performed in six rats bearing mature teratomas and two rats with necrotic lesions on a microSPECT/CT device after injection of the tracer [{sup 99m}Tc]HYNIC-RGD [6-hydrazinonicotinic acid conjugated to cyclo(Arg-Gly-Asp-D-Phe-Lys)]. Correlative immunohistochemistry studies of human and mouse {alpha}{sub v}{beta}{sub 3} expression were performed. Cisplatin+ATRA induced differentiation of the xenografts. After 8 weeks, some glandular structures and mesenchymal cells were visible; in contrast, control tumours showed undifferentiated tissues. SA PET imaging showed that mature teratoma had very low avidity for {sup 18}F-FDG [mean standardised uptake value (SUV{sub mean}) = 0.48 {+-} 0.05] compared to untreated embryonal carcinoma (SUV{sub mean} = 0.92 {+-} 0.13) (p = 0.005). {alpha}{sub v}{beta}{sub 3} imaging accurately distinguished mature teratoma (tumour to muscle ratio = 4.29 {+-} 1.57) from necrosis (tumour to muscle ratio = 1.3 {+-} 0.26) (p = 0.0002). Immunohistochemistry studies showed that {alpha}{sub v}{beta}{sub 3} integrin expression was strong in the glandular structures of mature teratoma lesions and negative in host stroma. Imaging {alpha}{sub v}{beta}{sub 3} integrin accurately distinguished mature teratoma from

  12. CONGENITAL ORBITAL TERATOMA

    African Journals Online (AJOL)

    was done without contrast and 3mm/5mm/10mm slices were obtained to cover the orbit, skull base and brain. The findings included a soft tissue mass arising from the orbit. The left eye ball was extra orbital. There was no defect .... love's Short Practice of Surgery. 7 Edition,. Levis London, 1997; 45-64. 2. Orbital tumor Part 1, ...

  13. Accurately localizing the thyroid tissue in mature cystic teratoma of ovary by single-photon emission computerized tomography/computerized tomography

    International Nuclear Information System (INIS)

    Demir, Yusuf; Üçler, Rıfkı; Alkiş, İsmet; Bulut, Gülay

    2015-01-01

    A 30-year-old woman with hyperthyroidism was admitted to hospital. Although increased thyroid function was found, the gland was normal in ultrasonography (USG). Additionally, thyroid iodine uptake and Tc-99m pertechnetate scintigraphy was normal. Abdomen USG detected a cystic pelvic mass in left ovary. A whole-body scan was performed 48 hours after oral ingestion of 29.6 MBq (0.8 mCi) I-131 (iodine-131) revealed a round structure located to the left lower abdomen. Iodine uptake was detected in this cyst which was compatible with functional thyroid tissue demonstrated by SPECT/CT. The patient was underwent surgical operation and histopathology confirmed mature cystic teratoma. Accurate localization and depiction of thyroid tissue in ovary mass was provided with SPECT/CT

  14. Conditional inactivation of p53 in mouse ovarian surface epithelium does not alter MIS driven Smad2-dominant negative epithelium-lined inclusion cysts or teratomas.

    Directory of Open Access Journals (Sweden)

    Suzanne M Quartuccio

    through qPCR analysis, characterized by teratoma-like lesions implicating Smad signaling in teratoma development.

  15. Bortezomib-based vs non-bortezomib-based post-transplantation treatment in multiple myeloma patients: a systematic review and meta-analysis of Phase III randomized controlled trials

    Directory of Open Access Journals (Sweden)

    Liu XP

    2015-06-01

    Full Text Available Xiaoping Liu,1 Colin K He,2 Xiangyu Meng,1 Li He,1 Kaili Li,1 Qing Liang,1 Liang Shao,1 Shangqin Liu1 1Department of Hematology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, People’s Republic of China; 2Orient Health Care, NYC, USA Objective: To evaluate the efficacy and safety of bortezomib-based vs non-bortezomib-based post-transplantation therapy in patients with multiple myeloma.Methods: Data of relevant randomized controlled trials assessing the effect of bortezomib as post-transplantation consolidation or maintenance therapy was obtained through a comprehensive search. The outcome measures included response rate, progression-free survival, overall survival, and adverse events (AEs. The hazard ratio (HR, Cochran-Mantel-Haenszel odds ratio (OR, and 95% confidence interval (95% CI were applied to evaluate the effect of bortezomib in relation to the end points such as progression-free survival, overall survival, response rate, and AEs.Results: Three randomized controlled trials comprising 1,518 participants were included in this study. Pooled ORs for the rates of overall response, and complete response and near complete response, were 1.85 and 1.75, respectively. Pooled HR for progression-free survival favored bortezomib-based therapy over non-bortezomib-based therapy (0.73, 95% CI: 0.67–0.81, while no statistically significant difference could be found between the two groups regarding the pooled HR for 3-year overall survival. Moreover, incidence rates of overall adverse events and grade 3 and 4 peripheral neuropathy were similar in the bortezomib-based groups and the non-bortezomib-based groups (P=0.12 and P=0.41, respectively. The corresponding cumulative meta-analyses of the rates of overall response rate, complete response and near complete response, and grades 3 and 4 peripheral neuropathy supported the superiority of bortezomib-based maintenance therapy over consolidation therapy.Conclusion: Bortezomib-based therapy after

  16. Use of External Cephalic Version and Amnioreduction in the Delivery of a Fetal Demise with Macrocephaly Secondary to Massive Intracranial Teratoma.

    Science.gov (United States)

    Blitz, Matthew J; Greeley, Elizabeth; Tam, Hima Tam; Rochelson, Burton

    2015-04-01

    Introduction Congenital intracranial tumors are rare and often incidentally diagnosed on routine ultrasound. We report a case of a fetal demise with a massive intracranial teratoma at 25 weeks of gestation and the management of her delivery in the setting of macrocephaly, breech presentation, and polyhydramnios. Case A 31-year-old G3P1011 woman at 25 weeks' gestation presented with a recent fetal demise and a fetal intracranial tumor first identified at 16 weeks' gestational age. The patient had declined termination of pregnancy. Biometry was consistent with 24 weeks' gestation, except for a head circumference of 394.4 mm consistent with 39 weeks' gestation. The fetus was in a breech presentation. An external cephalic version (ECV) was successfully performed under epidural anesthesia and an amnioreduction was then performed to stabilize the fetal position. Immediate induction of labor and vaginal delivery followed. Discussion ECV and amnioreduction may help facilitate delivery in cases of fetal demise complicated by macrocephaly, malpresentation, and polyhydramnios.

  17. Use of External Cephalic Version and Amnioreduction in the Delivery of a Fetal Demise with Macrocephaly Secondary to Massive Intracranial Teratoma

    Directory of Open Access Journals (Sweden)

    Matthew J. Blitz

    2015-04-01

    Full Text Available Introduction - Congenital intracranial tumors are rare and often incidentally diagnosed on routine ultrasound. We report a case of a fetal demise with a massive intracranial teratoma at 25 weeks of gestation and the management of her delivery in the setting of macrocephaly, breech presentation, and polyhydramnios. Case - A 31-year-old G3P1011 woman at 25 weeks' gestation presented with a recent fetal demise and a fetal intracranial tumor first identified at 16 weeks' gestational age. The patient had declined termination of pregnancy. Biometry was consistent with 24 weeks' gestation, except for a head circumference of 394.4 mm consistent with 39 weeks' gestation. The fetus was in a breech presentation. An external cephalic version (ECV was successfully performed under epidural anesthesia and an amnioreduction was then performed to stabilize the fetal position. Immediate induction of labor and vaginal delivery followed. Discussion - ECV and amnioreduction may help facilitate delivery in cases of fetal demise complicated by macrocephaly, malpresentation, and polyhydramnios.

  18. The presence of centrioles and centrosomes in ovarian mature cystic teratoma cells suggests human parthenotes developed in vitro can differentiate into mature cells without a sperm centriole.

    Science.gov (United States)

    Lee, Bo Yon; Shim, Sang Woo; Kim, Young Sun; Kim, Seung Bo

    2011-11-18

    In most animals, somatic cell centrosomes are inherited from the centriole of the fertilizing spermatozoa. The oocyte centriole degenerates during oogenesis, and completely disappears in metaphase II. Therefore, the embryos generated by in vitro parthenogenesis are supposed to develop without any centrioles. Exceptional acentriolar and/or acentrosomal developments are possible in mice and in some experimental cells; however, in most animals, the full developmental potential of parthenogenetic cells in vitro and the fate of their centrioles/centrosomes are not clearly understood. To predict the future of in vitro human parthenogenesis, we explored the centrioles/centrosomes in ovarian mature cystic teratoma cells by immunofluorescent staining and transmission electron microscopy. We confirmed the presence of centrioles and centrosomes in these well-known parthenogenetic ovarian tumor cells. Our findings clearly demonstrate that, even without a sperm centriole, parthenotes that develop from activated oocytes can produce their own centrioles/centrosomes, and can even develop into the well-differentiated mature tissue. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Incidental finding of ovarian teratoma on post-therapy scan for papillary thyroid cancer and impact of SPECT/CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Jammah, Anwar Ali, E-mail: dranwarjammah@hotmail.com [Department of Medicine, King Saud University, Riyadh (Saudi Arabia); Driedger, Albert; Rachinsky, Irina [Department of Nuclear Medicine, University of Western Ontario, (Canada)

    2011-10-15

    A 41-year old woman post thyroidectomy and neck dissection is presented in this case. She initially presented goiter and an enlarged cervical lymph node. She had no family history of cancer or radiation therapy. She had total thyroidectomy and found to have papillary thyroid cancer (T4N1M0). Histopathology report revealed multifocal classical papillary thyroid carcinoma with lymphovascular invasion, extra-thyroidal extension, and positive lymph nodes. She was treated with 6.5 Gigabecquerel (GBq) of {sup 131}Iodine. Whole-body scan showed uptake in the neck and large focus in the left lower abdomen. Single-photon emission computed tomography SPECT/CT demonstrated a round shaped mass in the left pelvis. Pathology revealed cystic teratoma with benign thyroid tissue (struma ovarii), and no malignancy. Two months later, she had the second treatment with 5.5 GBq {sup 131}Iodine. Her follow-up stimulated and non-stimulated thyroglobulin levels were significantly lower, and there was no abnormal uptake in the follow- -up scan (author)

  20. Autocrine growth induced by the insulin-related factor in the insulin-independent teratoma cell line 1246-3A

    International Nuclear Information System (INIS)

    Yamada, Yukio; Serrero, G.

    1988-01-01

    An insulin-independent teratoma-derived cell line, called 1246-3A, has been isolated from the adipogenic cell line 1246, which stringently requires insulin for proliferation. The 1246-3A cell line, which can proliferate in the absence of exogenous insulin, produces in its conditioned medium a growth factor similar to pancreatic insulin by its biological and immunological properties. This factor, called insulin-related factor (IRF), was purified and iodinated to study its binding to cell surface receptors. 125 I-labeled IRF binding to intact 1246-3A cells is lower than to 1246 cells. Cell surface binding can be restored by culturing the 1246-3A cells in the presence of an anti-porcine insulin monoclonal antibody of by acid prewash of the cells prior to performing the binding. Scatchard analysis of binding indicates that IRF secreted by the 1246-3A cells partially occupies high-affinity binding sites on the producer cells. Moreover, insulin monoclonal antibody inhibits the proliferation of the IRF-producing 1246-3A cells, suggesting that these cells are dependent on the secreted IRF for growth in culture. The authors conclude that the insulin-related factor secreted by the insulin-independent 1246-3A cells stimulates their proliferation in an autocrine fashion

  1. EBV-associated post-transplantation B-cell lymphoproliferative disorder following allogenic stem cell transplantation for acute lymphoblastic leukaemia: tumor regression after reduction of immunosuppression - a case report

    Directory of Open Access Journals (Sweden)

    Niedobitek Gerald

    2010-03-01

    Full Text Available Abstract Epstein-Barr virus (EBV-associated B-cell post-transplantation lymphoproliferative disorder (PTLD is a severe complication following stem cell transplantation. This is believed to occur as a result of iatrogenic immunosuppression leading to a relaxation of T-cell control of EBV infection and thus allowing viral reactivation and proliferation of EBV-infected B-lymphocytes. In support of this notion, reduction of immunosuppressive therapy may lead to regression of PTLD. We present a case of an 18-year-old male developing a monomorphic B-cell PTLD 2 months after receiving an allogenic stem cell transplant for acute lymphoblastic leukemia. Reduction of immunosuppressive therapy led to regression of lymphadenopathy. Nevertheless, the patient died 3 months afterwards due to extensive graft-vs.-host-disease and sepsis. As a diagnostic lymph node biopsy was performed only after reduction of immunosuppressive therapy, we are able to study the histopathological changes characterizing PTLD regression. We observed extensive apoptosis of blast cells, accompanied by an abundant infiltrate comprising predominantly CD8-positive, Granzyme B-positive T-cells. This observation supports the idea that regression of PTLD is mediated by cytotoxic T-cells and is in keeping with the observation that T-cell depletion, represents a major risk factor for the development of PTLD.

  2. Unilateral follicular variant of papillary thyroid carcinoma with unique KRAS mutation in struma ovarii in bilateral ovarian teratoma: a rare case report

    Directory of Open Access Journals (Sweden)

    Stanojevic Boban

    2012-06-01

    Full Text Available Abstract Background Struma ovarii (SO is a rare form of ovarian mature teratoma in which thyroid tissue is the predominant element. Because of its rarity, the differential diagnosis between benign and malignant SO has not been clearly defined. It is believed that malignant transformation of SO has similar molecular features with and its prognosis corresponds to that of malignant tumors originating in the thyroid. Case presentation We report 35-year-old woman with bilateral ovarian cysts incidentally detected by ultrasound during the first trimester of pregnancy. Four months after delivery of a healthy child without complication she was admitted to the hospital for acute abdominal pain. Laparoscopic left adnexectomy was performed initially in a regional hospital; right cystectomy was done later in a specialized clinic. Intraoperative frozen section and a final pathology revealed that the cyst from the left ovary was composed of mature teratomatous elements, normal thyroid tissue (>50% and a non-encapsulated focus of follicular variant of papillary thyroid carcinoma (PTC. Normal and cancerous thyroid tissues were tested for BRAF and RAS mutations by direct sequencing, and for RET/PTC rearrangements by RT-PCR/Southern blotting. A KRAS codon 12 mutation, the GGT → GTT transversion, corresponding to the Gly → Val amino acid change was identified in the absence of other genetic alterations commonly found in PTC. Conclusion To the best of our knowledge, this is the first time this mutation is described in a papillary thyroid carcinoma arising in struma in the ovarii. This finding provides further evidence that even rare mutations specific for PTC may occur in such tumors. Molecular testing may be a useful adjunct to common differential diagnostic methods of thyroid malignancy in SO.

  3. Incidence of Posttransplantation Diabetes Mellitus in De Novo Kidney Transplant Recipients Receiving Prolonged-Release Tacrolimus-Based Immunosuppression With 2 Different Corticosteroid Minimization Strategies: ADVANCE, A Randomized Controlled Trial.

    Science.gov (United States)

    Mourad, Georges; Glyda, Maciej; Albano, Laetitia; Viklický, Ondrej; Merville, Pierre; Tydén, Gunnar; Mourad, Michel; Lõhmus, Aleksander; Witzke, Oliver; Christiaans, Maarten H L; Brown, Malcolm W; Undre, Nasrullah; Kazeem, Gbenga; Kuypers, Dirk R J

    2017-08-01

    ADVANCE (NCT01304836) was a phase 4, multicenter, prospectively randomized, open-label, 24-week study comparing the incidence of posttransplantation diabetes mellitus (PTDM) with 2 prolonged-release tacrolimus corticosteroid minimization regimens. All patients received prolonged-release tacrolimus, basiliximab, mycophenolate mofetil and 1 bolus of intraoperative corticosteroids (0-1000 mg) as per center policy. Patients in arm 1 received tapered corticosteroids, stopped after day 10, whereas patients in arm 2 received no steroids after the intraoperative bolus. The primary efficacy variable was the diagnosis of PTDM as per American Diabetes Association criteria (2010) at any point up to 24 weeks postkidney transplantation. Secondary efficacy variables included incidence of composite efficacy failure (graft loss, biopsy-proven acute rejection or severe graft dysfunction: estimated glomerular filtration rate (Modification of Diet in Renal Disease-4) <30 mL/min per 1.73 m), acute rejection and graft and patient survival. The full-analysis set included 1081 patients (arm 1: n = 528, arm 2: n = 553). Baseline characteristics and mean tacrolimus trough levels were comparable between arms. Week 24 Kaplan-Meier estimates of PTDM were similar for arm 1 versus arm 2 (17.4% vs 16.6%; P = 0.579). Incidence of composite efficacy failure, graft and patient survival, and mean estimated glomerular filtration rate were also comparable between arms. Biopsy-proven acute rejection and acute rejection were significantly higher in arm 2 versus arm 1 (13.6% vs 8.7%, P = 0.006 and 25.9% vs 18.2%, P = 0.001, respectively). Tolerability profiles were comparable between arms. A prolonged-release tacrolimus, basiliximab, and mycophenolate mofetil immunosuppressive regimen is efficacious, with a low incidence of PTDM and a manageable tolerability profile over 24 weeks of treatment. A lower incidence of biopsy-proven acute rejection was seen in patients receiving corticosteroids tapered over 10

  4. T Cell-Replete Peripheral Blood Haploidentical Hematopoietic Cell Transplantation with Post-Transplantation Cyclophosphamide Results in Outcomes Similar to Transplantation from Traditionally Matched Donors in Active Disease Acute Myeloid Leukemia.

    Science.gov (United States)

    How, Joan; Slade, Michael; Vu, Khoan; DiPersio, John F; Westervelt, Peter; Uy, Geoffrey L; Abboud, Camille N; Vij, Ravi; Schroeder, Mark A; Fehniger, Todd A; Romee, Rizwan

    2017-04-01

    Outcomes for patients with acute myeloid leukemia (AML) who fail to achieve complete remission remain poor. Hematopoietic cell transplantation (HCT) has been shown to induce long-term survival in AML patients with active disease. HCT is largely performed with HLA-matched unrelated or HLA-matched related donors. Recently, HCT with HLA-haploidentical related donors has been identified as a feasible option when HLA-matched donors are not immediately available. However, there are little data comparing outcomes for AML patients with active disease who receive haploidentical versus traditionally matched HCT. We retrospectively analyzed data from 99 AML patients with active disease undergoing allogeneic HCT at a single institution. Forty-three patients received unrelated donor HCT, 32 patients received matched related donor HCT, and 24 patients received peripheral blood haploidentical HCT with post-transplantation cyclophosphamide. We found no significant differences between treatment groups in terms of overall survival (OS), event-free survival, transplantation-related mortality, cumulative incidence of relapse, and cumulative incidence of acute and chronic graft-versus-host disease (GVHD). We performed univariate regression analysis of variables that modified OS in all patients and found only younger age at transplantation and development of chronic GVHD significantly improved outcome. Although limited by our relatively small sample size, these results indicate that haploidentical HCT in active AML patients have comparable outcomes to HCT with traditionally matched donors. Haploidentical HCT can be considered in this population of high-risk patients when matched donors are unavailable or when wait times for transplantation are unacceptably long. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  5. Fusion of the SUMO/Sentrin-specific protease 1 gene SENP1 and the embryonic polarity-related mesoderm development gene MESDC2 in a patient with an infantile teratoma and a constitutional t(12;15)(q13;q25).

    NARCIS (Netherlands)

    Veltman, I.M.; Basten-Vreede, L.A.J.; Cheng, J.; Looijenga, L.H.J.; Janssen, H.A.P.; Schoenmakers, E.F.P.M.; Yeh, E.T.; Geurts van Kessel, A.H.M.

    2005-01-01

    Recently, we identified a patient with an infantile sacrococcygeal teratoma and a constitutional t(12;15)(q13;q25). Here, we show that, as a result of this chromosomal translocation, the SUMO/Sentrin-specific protease 1 gene (SENP1) on chromosome 12 and the embryonic polarity-related mesoderm

  6. Nutrition in children posttransplantation | Goddard | South African ...

    African Journals Online (AJOL)

    Nutrition support is a vitally important issue in the pretransplantation period. Once a child has been assessed and placed on a list for transplantation the child must see a dietitian to optimise the child's nutritional status as this is vital to improve the outcome at surgery. Children with chronic liver disease who are candidates for ...

  7. Posttransplantation Disseminated Coccidioidomycosis Acquired from Donor Lungs

    OpenAIRE

    Miller, Melissa B.; Hendren, Ryan; Gilligan, Peter H.

    2004-01-01

    A North Carolinian developed fatal coccidioidomycosis immediately after bilateral lung transplantation. The donor had previously traveled to Mexico, and the recipient had no travel history to an area where Coccidioides immitis is endemic. Immunosuppresive therapy of the transplant recipient likely reactivated latent Coccidioides infection in the donor lungs, leading to posttransplant coccidioidomycosis.

  8. Mutlifocal osseous posttransplantation lymphoproliferative disorder: case report

    International Nuclear Information System (INIS)

    Lo, Ryan; Michalicek, Zachary; Lazarus, Martin

    2015-01-01

    Posttransplant lymphoproliferative disorder (PTLD) is a known complication of organ transplantation, but musculoskeletal involvement of PTLD remains very rare. We present a case of recurrent PTLD of the bone in a heart transplant patient that was misdiagnosed as gout for several years. There are only a few cases of osseous PTLD in the literature, and we hope to better characterize its imaging findings on multiple imaging modalities. (orig.)

  9. Post-transplantation Development of Food Allergies.

    Science.gov (United States)

    Newman, Erik N; Firszt, Rafael

    2018-01-29

    The development of food allergies is increasingly being recognized as a post-solid organ transplant complication. In this article, we review the spectrum of post-transplant food allergy development and the proposed mechanisms for de novo food allergies and the clinical significance they pose. The development of new food allergies is disproportionately associated with pediatric liver transplants, where it occurs in up to 38% of select populations. The mechanism of food allergy development is not completely understood; however, it is likely promoted by unbalanced immune suppression. De novo food allergy development is a common complication of solid organ transplants with the highest risk occurring in pediatric liver transplant recipients. There are likely multiple mechanisms for food allergy development including passive transfer of membrane-bound IgE and lymphocytes from donor to recipient, as well as loss of food tolerance and active development of new food allergies. The optimal management of food allergies following organ transplants has not been well researched but may include changing the immune suppression regimen if the food allergy does not resolve without intervention.

  10. Mutlifocal osseous posttransplantation lymphoproliferative disorder: case report

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Ryan [University of Chicago, Department of Radiology, Chicago, IL (United States); Michalicek, Zachary [Northshore University Healthsystems, Department of Pathology, Evanston, IL (United States); Lazarus, Martin [Northshore University Healthsystems, Department of Radiology, Evanston, IL (United States)

    2015-02-14

    Posttransplant lymphoproliferative disorder (PTLD) is a known complication of organ transplantation, but musculoskeletal involvement of PTLD remains very rare. We present a case of recurrent PTLD of the bone in a heart transplant patient that was misdiagnosed as gout for several years. There are only a few cases of osseous PTLD in the literature, and we hope to better characterize its imaging findings on multiple imaging modalities. (orig.)

  11. Sacrococcygeal teratoma: management and outcomes

    African Journals Online (AJOL)

    AFP to be normalized after SCT resection is about 9 months [14]. Recurrence after resection varies from 2 to 35%. This may result from incomplete surgical excision with the presence of microscopic residues, nonresection of the entire coccyx, and/or tumor spillage [15,16]. Although the postnatal mortality of SCTs is low [17],.

  12. Stellar formation

    CERN Document Server

    Reddish, V C

    1978-01-01

    Stellar Formation brings together knowledge about the formation of stars. In seeking to determine the conditions necessary for star formation, this book examines questions such as how, where, and why stars form, and at what rate and with what properties. This text also considers whether the formation of a star is an accident or an integral part of the physical properties of matter. This book consists of 13 chapters divided into two sections and begins with an overview of theories that explain star formation as well as the state of knowledge of star formation in comparison to stellar structure

  13. Galaxy formation

    International Nuclear Information System (INIS)

    Silk, J.; Di Cintio, A.; Dvorkin, I.

    2014-01-01

    Galaxy formation is at the forefront of observation and theory in cosmology. An improved understanding is essential for improving our knowledge both of the cosmological parameters, of the contents of the universe, and of our origins. In these lectures intended for graduate students, galaxy formation theory is reviewed and confronted with recent observational issues. In lecture 1, the following topics are presented: star formation considerations, including IMF, star formation efficiency and star formation rate, the origin of the galaxy luminosity function, and feedback in dwarf galaxies. In lecture 2, we describe formation of disks and massive spheroids, including the growth of supermassive black holes, negative feedback in spheroids, the AGN-star formation connection, star formation rates at high redshift and the baryon fraction in galaxies.

  14. Formative (measurement)

    NARCIS (Netherlands)

    Fassott, G.; Henseler, Jörg; Cooper, C.; Lee, N.; Farrell, A.

    2015-01-01

    When using measurement models with multiple indicators, researchers need to decide about the epistemic relationship between the latent variable and its indicators. In this article, we describe the nature, the estimation, the characteristics, and the validity assessment of formative measurement

  15. Cement Formation

    DEFF Research Database (Denmark)

    Telschow, Samira; Jappe Frandsen, Flemming; Theisen, Kirsten

    2012-01-01

    Cement production has been subject to several technological changes, each of which requires detailed knowledge about the high multiplicity of processes, especially the high temperature process involved in the rotary kiln. This article gives an introduction to the topic of cement, including...... an overview of cement production, selected cement properties, and clinker phase relations. An extended summary of laboratory-scale investigations on clinkerization reactions, the most important reactions in cement production, is provided. Clinker formations by solid state reactions, solid−liquid and liquid......−liquid reactions are discussed, as are the influences of particles sizes on clinker phase formation. Furthermore, a mechanism for clinker phase formation in an industrial rotary kiln reactor is outlined....

  16. Star formation

    International Nuclear Information System (INIS)

    Woodward, P.R.

    1978-01-01

    Theoretical models of star formation are discussed beginning with the earliest stages and ending in the formation of rotating, self-gravitating disks or rings. First a model of the implosion of very diffuse gas clouds is presented which relies upon a shock at the edge of a galactic spiral arm to drive the implosion. Second, models are presented for the formation of a second generation of massive stars in such a cloud once a first generation has formed. These models rely on the ionizing radiation from massive stars or on the supernova shocks produced when these stars explode. Finally, calculations of the gravitational collapse of rotating clouds are discussed with special focus on the question of whether rotating disks or rings are the result of such a collapse. 65 references

  17. Galaxy Formation

    DEFF Research Database (Denmark)

    Sparre, Martin

    Galaxy formation is an enormously complex discipline due to the many physical processes that play a role in shaping galaxies. The objective of this thesis is to study galaxy formation with two different approaches: First, numerical simulations are used to study the structure of dark matter and how...... galaxies form stars throughout the history of the Universe, and secondly it is shown that observations of gamma-ray bursts (GRBs) can be used to probe galaxies with active star formation in the early Universe. A conclusion from the hydrodynamical simulations is that the galaxies from the stateof...... is important, since it helps constraining chemical evolution models at high redshift. A new project studying how the population of galaxies hosting GRBs relate to other galaxy population is outlined in the conclusion of this thesis. The core of this project will be to quantify how the stellar mass function...

  18. Comet formation

    Science.gov (United States)

    Blum, J.

    2014-07-01

    There has been vast progress in our understanding of planetesimal formation over the past decades, owing to a number of laboratory experiments as well as to refined models of dust and ice agglomeration in protoplanetary disks. Coagulation rapidly forms cm-sized ''pebbles'' by direct sticking in collisions at low velocities (Güttler et al. 2010; Zsom et al. 2010). For the further growth, two model approaches are currently being discussed: (1) Local concentration of pebbles in nebular instabilities until gravitational instability occurs (Johansen et al. 2007). (2) A competition between fragmentation and mass transfer in collisions among the dusty bodies, in which a few ''lucky winners'' make it to planetesimal sizes (Windmark et al. 2012a,b; Garaud et al. 2013). Predictions of the physical properties of the resulting bodies in both models allow a distinction of the two formation scenarios of planetesimals. In particular, the tensile strength (i.e, the inner cohesion) of the planetesimals differ widely between the two models (Skorov & Blum 2012; Blum et al. 2014). While model (1) predicts tensile strengths on the order of ˜ 1 Pa, model (2) results in rather compactified dusty bodies with tensile strengths in the kPa regime. If comets are km-sized survivors of the planetesimal-formation era, they should in principle hold the secret of their formation process. Water ice is the prime volatile responsible for the activity of comets. Thermophysical models of the heat and mass transport close to the comet-nucleus surface predict water-ice sublimation temperatures that relate to maximum sublimation pressures well below the kPa regime predicted for formation scenario (2). Model (1), however, is in agreement with the observed dust and gas activity of comets. Thus, a formation scenario for cometesimals involving gravitational instability is favored (Blum et al. 2014).

  19. Planet Formation

    Science.gov (United States)

    Podolak, Morris

    2018-04-01

    Modern observational techniques are still not powerful enough to directly view planet formation, and so it is necessary to rely on theory. However, observations do give two important clues to the formation process. The first is that the most primitive form of material in interstellar space exists as a dilute gas. Some of this gas is unstable against gravitational collapse, and begins to contract. Because the angular momentum of the gas is not zero, it contracts along the spin axis, but remains extended in the plane perpendicular to that axis, so that a disk is formed. Viscous processes in the disk carry most of the mass into the center where a star eventually forms. In the process, almost as a by-product, a planetary system is formed as well. The second clue is the time required. Young stars are indeed observed to have gas disks, composed mostly of hydrogen and helium, surrounding them, and observations tell us that these disks dissipate after about 5 to 10 million years. If planets like Jupiter and Saturn, which are very rich in hydrogen and helium, are to form in such a disk, they must accrete their gas within 5 million years of the time of the formation of the disk. Any formation scenario one proposes must produce Jupiter in that time, although the terrestrial planets, which don't contain significant amounts of hydrogen and helium, could have taken longer to build. Modern estimates for the formation time of the Earth are of the order of 100 million years. To date there are two main candidate theories for producing Jupiter-like planets. The core accretion (CA) scenario supposes that any solid materials in the disk slowly coagulate into protoplanetary cores with progressively larger masses. If the core remains small enough it won't have a strong enough gravitational force to attract gas from the surrounding disk, and the result will be a terrestrial planet. If the core grows large enough (of the order of ten Earth masses), and the disk has not yet dissipated, then

  20. Galaxy Formation

    CERN Document Server

    Longair, Malcolm S

    2008-01-01

    This second edition of Galaxy Formation is an up-to-date text on astrophysical cosmology, expounding the structure of the classical cosmological models from a contemporary viewpoint. This forms the background to a detailed study of the origin of structure and galaxies in the Universe. The derivations of many of the most important results are derived by simple physical arguments which illuminate the results of more advanced treatments. A very wide range of observational data is brought to bear upon these problems, including the most recent results from WMAP, the Hubble Space Telescope, galaxy surveys like the Sloan Digital Sky Survey and the 2dF Galaxy Redshift Survey, studies of Type 1a supernovae, and many other observations.

  1. Galaxy formation

    International Nuclear Information System (INIS)

    Gribbin, J.

    1979-01-01

    The current debate on the origin and evolution of galaxies is reviewed and evidence to support the so-called 'isothermal' and 'adiabatic' fluctuation models considered. It is shown that new theories have to explain the formation of both spiral and elliptical galaxies and the reason for their differences. It is stated that of the most recent models the best indicates that rotating spiral galaxies are formed naturally when gas concentrates in the centre of a great halo and forms stars while ellipticals are explained by later interactions between spiral galaxies and merging, which can cancel out the rotation while producing an elliptical galaxy in which the stars, coming from two original galaxies, follow very elliptical, anisotropic orbits. (UK)

  2. Habit formation.

    Science.gov (United States)

    Smith, Kyle S; Graybiel, Ann M

    2016-03-01

    Habits, both good ones and bad ones, are pervasive in animal behavior. Important frameworks have been developed to understand habits through psychological and neurobiological studies. This work has given us a rich understanding of brain networks that promote habits, and has also helped us to understand what constitutes a habitual behavior as opposed to a behavior that is more flexible and prospective. Mounting evidence from studies using neural recording methods suggests that habit formation is not a simple process. We review this evidence and take the position that habits could be sculpted from multiple dissociable changes in neural activity. These changes occur across multiple brain regions and even within single brain regions. This strategy of classifying components of a habit based on different brain signals provides a potentially useful new way to conceive of disorders that involve overly fixed behaviors as arising from different potential dysfunctions within the brain's habit network.

  3. Habit formation

    Science.gov (United States)

    Smith, Kyle S.; Graybiel, Ann M.

    2016-01-01

    Habits, both good ones and bad ones, are pervasive in animal behavior. Important frameworks have been developed to understand habits through psychological and neurobiological studies. This work has given us a rich understanding of brain networks that promote habits, and has also helped us to understand what constitutes a habitual behavior as opposed to a behavior that is more flexible and prospective. Mounting evidence from studies using neural recording methods suggests that habit formation is not a simple process. We review this evidence and take the position that habits could be sculpted from multiple dissociable changes in neural activity. These changes occur across multiple brain regions and even within single brain regions. This strategy of classifying components of a habit based on different brain signals provides a potentially useful new way to conceive of disorders that involve overly fixed behaviors as arising from different potential dysfunctions within the brain's habit network. PMID:27069378

  4. Mature cystic teratomas: Relationship between histopathological ...

    African Journals Online (AJOL)

    2014-08-09

    Aug 9, 2014 ... [4-6] The detection rate of tumor markers is low, although high levels of CA-19.9 are common in MCT cases.[7] MCTs are composed of endodermal, mesodermal and ectodermal derivatives.[8] Some clinical situations can be associated with the composition of MCT, such as a stromal carcinoid ovarian tumor ...

  5. 'Biracial'-Looking Twins: A New Twin Type?/Twin Research: Twins with Cystic Teratomas; Sleep Quality and Body Mass Index; Previable Membrane Rupture/Print and Online Reports: Twins Born to a Sister Surrogate; NASA Twin Study; African-Cosmopolitan Twin Fashion Inspirations; Triplet Hockey Stars.

    Science.gov (United States)

    Segal, Nancy L

    2017-06-01

    Dizygotic (DZ) co-twins born to mothers and fathers from different racial or ethnic backgrounds often resemble one parent much more than the other. As such, these pairs comprise a unique subset of twins for investigating how others' responses to their different looks may affect their personalities and self-esteem. This article describes some of these twin pairs and some challenges of raising them, and suggests ways they may be used in research. Next, recent twin research on cystic teratomas, relations between sleep quality and body mass index, and previable membrane rupture is described. The final section concerns twins, twin studies, and related events in the media, namely: twins born to a sister surrogate, the NASA twin investigation, inspiring African-Cosmopolitan twins in fashion, and triplet Hockey Stars.

  6. Molecular Mechanisms to Control Post-Transplantation Hepatitis B Recurrence

    Directory of Open Access Journals (Sweden)

    Akinobu Takaki

    2015-07-01

    Full Text Available Hepatitis B often progresses to decompensated liver cirrhosis requiring orthotopic liver transplantation (OLT. Although newer nucleos(tide analogues result in >90% viral and hepatitis activity control, severely decompensated patients still need OLT because of drug-resistant virus, acute exacerbation, or hepatocellular carcinoma. Acute hepatitis B is also an indication for OLT, because it can progress to fatal acute liver failure. After OLT, the hepatitis B recurrence rate is >80% without prevention, while >90% of transplant recipients are clinically controlled with combined hepatitis B immunoglobulin (HBIG and nucleos(tide analogue treatment. However, long-term HBIG administration is associated with several unresolved issues, including limited availability and extremely high cost; therefore, several treatment protocols with low-dose HBIG, combined with nucleos(tide analogues, have been investigated. Another approach is to induce self-producing anti-hepatitis B virus (HBV antibodies using an HBV envelope (HBs antigen vaccine. Patients who are not HBV carriers, such as those with acutely infected liver failure, are good candidates for vaccination. For chronic HBV carrier liver cirrhosis patients, a successful vaccine response can only be achieved in selected patients, such as those treated with experimentally reduced immunosuppression protocols. The present protocol for post-OLT HBV control and the future prospects of newer treatment strategies are reviewed.

  7. A typical aspects of intrathoracic posttransplantation lymphoproliferative disorders

    International Nuclear Information System (INIS)

    Beigelman, C.; Leblond, V.; Suberbielle, C.; Lenoir, S.; Dorent, R.; Grenier, P.

    1995-01-01

    Posttransplant lymphoproliferative disorders (PTLD), developing after immunosuppressive therapy in human organ-graft recipients, are, for the most part, Epstein-Barr virus-induced. The earlier the diagnosis is made, the greater the potential for reversibility. The chest radiographs and CT scans of 10 patients with thoracic locations of PTLD were reviewed. Mediastinal and hilar adenopathy, pulmonary nodules, and pleural thickening or effusion were encountered. The incidence of partial resolution with clinical remission appears to be noteworthy, and in all likelihood is related to the extensive necrosis that is frequently seen. Slow regression, transitory deterioration in one case, and localization only on the graft side in two cases, were observed. These morphological and evolutionary peculiarities must be known in order to optimize the diagnosis, and thus the prognosis, of these very original disorders. (orig.)

  8. Rates of star formation

    International Nuclear Information System (INIS)

    Larson, R.B.

    1977-01-01

    It is illustrated that a theoretical understanding of the formation and evolution of galaxies depends on an understanding of star formation, and especially of the factors influencing the rate of star formation. Some of the theoretical problems of star formation in galaxies, some approaches that have been considered in models of galaxy evolution, and some possible observational tests that may help to clarify which processes or models are most relevant are reviewed. The material is presented under the following headings: power-law models for star formation, star formation processes (conditions required, ways of achieving these conditions), observational indications and tests, and measures of star formation rates in galaxies. 49 references

  9. Why adult formation

    Directory of Open Access Journals (Sweden)

    Andrej Justinek

    1997-01-01

    Full Text Available The article argues that the primary aim of adult formation is comprehensive personality development which is supposed to ensure quality existence in modern world. The article also suggests that formarion is a permanent process. Justinek puts special emphasis on adult formation methodology and defines fundamental formation styles which encourage independent action in individuals. Justinek differentiates between formation and education. methods and concludes that formation methods are related to the emotional sphere of personality, and education methods mostly to the rational. Justinek believes that formation of adults is based primarily on appropriate formation methodology.

  10. Formate Formation and Formate Conversion in Biological Fuels Production

    Directory of Open Access Journals (Sweden)

    Bryan R. Crable

    2011-01-01

    Full Text Available Biomethanation is a mature technology for fuel production. Fourth generation biofuels research will focus on sequestering CO2 and providing carbon-neutral or carbon-negative strategies to cope with dwindling fossil fuel supplies and environmental impact. Formate is an important intermediate in the methanogenic breakdown of complex organic material and serves as an important precursor for biological fuels production in the form of methane, hydrogen, and potentially methanol. Formate is produced by either CoA-dependent cleavage of pyruvate or enzymatic reduction of CO2 in an NADH- or ferredoxin-dependent manner. Formate is consumed through oxidation to CO2 and H2 or can be further reduced via the Wood-Ljungdahl pathway for carbon fixation or industrially for the production of methanol. Here, we review the enzymes involved in the interconversion of formate and discuss potential applications for biofuels production.

  11. FORMATION CONSTANTS AND THERMODYNAMIC ...

    African Journals Online (AJOL)

    KEY WORDS: Metal complexes, Schiff base ligand, Formation constant, DFT calculation ... best values for the formation constants of the proposed equilibrium model by .... to its positive charge distribution and the ligand deformation geometry.

  12. Theory of aurora formation

    International Nuclear Information System (INIS)

    Hasegawa, Akira.

    1975-04-01

    A new theory of aurora formation is presented based on Alfven wave-electron interaction. The theory explains consistently 1) the electron acceleration process, 2) the formation of auroral layers and 3) the long wave formation in the longitudinal direction. (auth.)

  13. Stages of ores formation

    International Nuclear Information System (INIS)

    Khasanov, A.Kh.

    1988-01-01

    Deposit formation (especially endogenous) is the complicated, multi-stage and long process. Establishment of deposit formation succession, age-specific correlations of minerals and aggregates have a high importance at solving genetic questions. Studying of minerals correlations and mineral aggregates, succession of their crystallization and other observations let restore the history of deposit formation, pick up in it different on duration and physical and chemical conditions stages

  14. Planet formation in Binaries

    OpenAIRE

    Thebault, Ph.; Haghighipour, N.

    2014-01-01

    Spurred by the discovery of numerous exoplanets in multiple systems, binaries have become in recent years one of the main topics in planet formation research. Numerous studies have investigated to what extent the presence of a stellar companion can affect the planet formation process. Such studies have implications that can reach beyond the sole context of binaries, as they allow to test certain aspects of the planet formation scenario by submitting them to extreme environments. We review her...

  15. Data format translation routines

    International Nuclear Information System (INIS)

    Burris, R.D.

    1981-02-01

    To enable the effective connection of several dissimilar computers into a network, modification of the data being passed from one computer to another may become necessary. This document describes a package of routines which permit the translation of data in PDP-8 formats to PDP-11 or DECsystem-10 formats or from PDP-11 format to DECsystem-10 format. Additional routines are described which permit the effective use of the translation routines in the environment of the Fusion Energy Division (FED) network and the Elmo Bumpy Torus (EBT) data base

  16. ENDF/B format

    International Nuclear Information System (INIS)

    Khalil, M.A.; Lemmel, H.D.

    1986-09-01

    This document is a brief user's description of the format of ENDF/B. This format, originally designed for the US Evaluated Nuclear Data File, is recommended for international use. This summary is an aid to customers of the IAEA Nuclear Data Section when receiving data retrievals in ENDF/B format. For more detailed information the report BNL-NCS-50496 (ENDF 102) should be consulted. An Appendix to the present document gives a summary of the format differences between ENDF/B-4 and ENDF/B-5. (author)

  17. Exploring Opponent Formats

    DEFF Research Database (Denmark)

    Jensen, Mads Møller; Rasmussen, Majken; Grønbæk, Kaj

    2013-01-01

    of how the opponent format and relationships impact a game are almost absent in current research. Thus, this paper aims to elucidate how the perception of a competition differs, depending on the opponent format, by presenting a game mechanic framework. The paper furthermore presents an interactive...... football-training platform, as well as games designed to explore the different opponent formats. The games are qualitatively evaluated to illuminate the qualities of and distinctions between different types of opponent formats, proposed by the framework terminology....

  18. ENDF/B Format

    International Nuclear Information System (INIS)

    Khalil, M.A.

    1975-01-01

    This document is a brief user's description of the format of ENDF/B, the evaluated neutron nuclear data library of the US National Nuclear Data Center. This summary is an aid to customers of the IAEA Nuclear Data Section when receiving data retrievals in ENDF/B format. For more detailed information the report BNL-50274 (ENDF-102) should be consulted. (author)

  19. Formation of multiple networks

    DEFF Research Database (Denmark)

    Magnani, Matteo; Rossi, Luca

    2013-01-01

    we introduce the first network formation model for multiple networks. Network formation models are among the most popular tools in traditional network studies, because of both their practical and theoretical impact. However, existing models are not sufficient to describe the generation of multiple...

  20. From Sermon Formation to Preacher Formation

    DEFF Research Database (Denmark)

    Gaarden, Marianne

    2016-01-01

    today is less about exercising the authority of an office and more about embodying authenticity. I argue that traditional homiletic education can benefit from implementing a learner-centered approach to teaching moving from sermon formation towards preacher formation, in order to develop and train...... preachers. This involves a learning strategy to ministry where theological skills, pastoral competences, and own personality are interwoven. Teaching here means facilitating a room of learning where teacher’s power and control is reduced, allowing the preacher to reflect upon own practice without being...... judged, evaluated, or critiqued. In this paper, I explain how a learner-centered approach to education works in practice and show how pastors experience the teaching method and the congregations’ positive response to their improvements. I shall present the results of a focus-group interview with pastors...

  1. Usage Record Format Recommendation

    CERN Document Server

    Nilsen, J.K.; Muller-Pfeerkorn, R

    2013-01-01

    For resources to be shared, sites must be able to exchange basic accounting and usage data in a common format. This document describes a common format which enables the exchange of basic accounting and usage data from different resources. This record format is intended to facilitate the sharing of usage information, particularly in the area of the accounting of jobs, computing, memory, storage and cloud usage but with a structure that allows an easy extension to other resources. This document describes the Usage Record components both in natural language form and annotated XML. This document does not address how these records should be used, nor does it attempt to dictate the format in which the accounting records are stored. Instead, it denes a common exchange format. Furthermore, nothing is said regarding the communication mechanisms employed to exchange the records, i.e. transport layer, framing, authentication, integrity, etc.

  2. Earth formation porosity log

    International Nuclear Information System (INIS)

    Smith, H.D.; Smith, M.P.; Schultz, W.E.

    1977-01-01

    A method for determining the porosity of earth formations in the vicinity of a cased well borehole is described, comprising the steps of: irradiating the earth formations in the vicinity of the cased well borehole with fast neutrons from a source of fast neutrons passed into the borehole; and generating a signal representative of the fast neutron population present in the well borehole at a location in the borehole, the signal is functionally related to the porosity of the earth formations in the vicinity of the borehole

  3. Manuel UNIMARC format bibliographique

    CERN Document Server

    2007-01-01

    This manual is the French translation of the second edition of UNIMARC Manual: bibliographic format published in English in 1994 and completed by 5 updates published from 1996 to 2005. This 5th French edition is composite. It reproduces identically a part of the 4th edition published in 2002 and, for the fields of the format modified in the Update 5, it offers a new more structured presentation. This is a handbook dedicated to French-speaking users of the UNIMARC format for bibliographic descriptions.

  4. Reconsidering formative measurement.

    Science.gov (United States)

    Howell, Roy D; Breivik, Einar; Wilcox, James B

    2007-06-01

    The relationship between observable responses and the latent constructs they are purported to measure has received considerable attention recently, with particular focus on what has become known as formative measurement. This alternative to reflective measurement in the area of theory-testing research is examined in the context of the potential for interpretational confounding and a construct's ability to function as a point variable within a larger model. Although these issues have been addressed in the traditional reflective measurement context, the authors suggest that they are particularly relevant in evaluating formative measurement models. On the basis of this analysis, the authors conclude that formative measurement is not an equally attractive alternative to reflective measurement and that whenever possible, in developing new measures or choosing among alternative existing measures, researchers should opt for reflective measurement. In addition, the authors provide guidelines for researchers dealing with existing formative measures. Copyright 2007 APA, all rights reserved.

  5. Isothermal Martensite Formation

    DEFF Research Database (Denmark)

    Villa, Matteo

    Isothermal (i.e. time dependent) martensite formation in steel was first observed in the 40ies of the XXth century and is still treated as an anomaly in the description of martensite formation which is considered as a-thermal (i.e. independent of time). Recently, the clarification of the mechanism...... of lattice strains provided fundamental information on the state of stress in the material and clarified the role of the strain energy on martensite formation. Electron backscatter diffraction revealed that the microstructure of the material and the morphology of martensite were independent on the cooling...... leading to isothermal kinetics acquired new practical relevance because of the identification of isothermal martensite formation as the most likely process responsible for enhanced performances of sub-zero Celsius treated high carbon steel products. In the present work, different iron based alloys...

  6. Cosmology and galaxy formation

    International Nuclear Information System (INIS)

    Rees, M.J.

    1977-01-01

    Implications of the massive halos and ''missing mass'' for galaxy formation are addressed; it is suggested that this mass consists of ''Population III'' stars that formed before the galaxies did. 19 references

  7. Fracturing formations in wells

    Energy Technology Data Exchange (ETDEWEB)

    Daroza, R A

    1964-05-15

    This well stimulation method comprises introducing through the well bore a low-penetrating, dilatant fluid, and subjecting the fluid to sufficient pressure to produce fractures in the formation. The fluid is permitted to remain in contact with the formation so as to become diluted by the formation fluids, and thereby lose its properties of dilatancy. Also, a penetrating fluid, containing a propping agent suspended therein, in introduced into contact with the fractures at a pressure substantially reduced with respect to that pressure which would have been required, prior to the fracturing operation performed using the low-penetrating dilatant fluid. The propping agent is deposited within the fractures, and thereafter, fluid production is resumed from the fractured formation. (2 claims)

  8. Star formation: Cosmic feast

    Science.gov (United States)

    Scaringi, Simone

    2017-03-01

    Low-mass stars form through a process known as disk accretion, eating up material that orbits in a disk around them. It turns out that the same mechanism also describes the formation of more massive stars.

  9. PCF File Format.

    Energy Technology Data Exchange (ETDEWEB)

    Thoreson, Gregory G [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-08-01

    PCF files are binary files designed to contain gamma spectra and neutron count rates from radiation sensors. It is the native format for the GAmma Detector Response and Analysis Software (GADRAS) package [1]. It can contain multiple spectra and information about each spectrum such as energy calibration. This document outlines the format of the file that would allow one to write a computer program to parse and write such files.

  10. Plant Formate Dehydrogenase

    Energy Technology Data Exchange (ETDEWEB)

    John Markwell

    2005-01-10

    The research in this study identified formate dehydrogenase, an enzyme that plays a metabolic role on the periphery of one-carbon metabolism, has an unusual localization in Arabidopsis thaliana and that the enzyme has an unusual kinetic plasticity. These properties make it possible that this enzyme could be engineered to attempt to engineer plants with an improved photosynthetic efficiency. We have produced transgenic Arabidopsis and tobacco plants with increased expression of the formate dehydrogenase enzyme to initiate further studies.

  11. Blistering and bubble formation

    International Nuclear Information System (INIS)

    Roth, J.

    1976-01-01

    Blister formation in metals has been observed during bombardment with inert-gas ions in the energy range between 1 and 2000 keV at doses of about 10 17 to 10 19 cm -2 . The changes in surface topography and the erosion yields were mainly studied in the scanning electron microscope (SEM). Additionally the release of the implanted gas during blister formation was observed. Recently measurements on single crystals were performed determining simultaneously the implantation profile, the total amount of trapped ions, the depth distribution of the induced lattice damage and the thickness of the covers of the blisters. In several stages of the formation process of blisters the implanted layer was observed in the transmission electron microscope (TEM) showing the formation of gas bubbles. Using the results of all these measurements in this review an attempt is made to develop a model of blister formation combining the effects of hydrostatic pressure in the gas bubbles and lateral stress due to volume swelling. (author)

  12. Vascular lumen formation.

    Science.gov (United States)

    Lammert, Eckhard; Axnick, Jennifer

    2012-04-01

    The vascular system developed early in evolution. It is required in large multicellular organisms for the transport of nutrients, oxygen, and waste products to and from tissues. The vascular system is composed of hollow tubes, which have a high level of complexity in vertebrates. Vasculogenesis describes the de novo formation of blood vessels, e.g., aorta formation in vertebrate embryogenesis. In contrast, angiogenesis is the formation of blood vessels from preexisting ones, e.g., sprouting of intersomitic blood vessels from the aorta. Importantly, the lumen of all blood vessels in vertebrates is lined and formed by endothelial cells. In both vasculogenesis and angiogenesis, lumen formation takes place in a cord of endothelial cells. It involves a complex molecular mechanism composed of endothelial cell repulsion at the cell-cell contacts within the endothelial cell cords, junctional rearrangement, and endothelial cell shape change. As the vascular system also participates in the course of many diseases, such as cancer, stroke, and myocardial infarction, it is important to understand and make use of the molecular mechanisms of blood vessel formation to better understand and manipulate the pathomechanisms involved.

  13. Meningococcal biofilm formation

    DEFF Research Database (Denmark)

    Lappann, M.; Haagensen, Janus Anders Juul; Claus, H.

    2006-01-01

    We show that in a standardized in vitro flow system unencapsulated variants of genetically diverse lineages of Neisseria meningitidis formed biofilms, that could be maintained for more than 96 h. Biofilm cells were resistant to penicillin, but not to rifampin or ciprofloxacin. For some strains......, microcolony formation within biofilms was observed. Microcolony formation in strain MC58 depended on a functional copy of the pilE gene encoding the pilus subunit pilin, and was associated with twitching of cells. Nevertheless, unpiliated pilE mutants formed biofilms showing that attachment and accumulation......X alleles was identified among genetically diverse meningococcal strains. PilX alleles differed in their propensity to support autoaggregation of cells in suspension, but not in their ability to support microcolony formation within biofilms in the continuous flow system....

  14. Tritiated ammonia formation

    International Nuclear Information System (INIS)

    Heung, L.K.

    1995-01-01

    When nitrogen was selected as the glovebox atmosphere for the Replacement Tritium Facility (RTF) at the Savannah River Site (SRS), a concern was raised as to the possibility of tritiated ammonia formation in the gloveboxes. Experimental data were produced to study the tritiated ammonia formation rate in a tritium and nitrogen mixture. A rate equation that closely simulates the experimental data was developed. This rate equation can be used to calculate the formation of tritiated ammonia from different concentrations of tritium and nitrogen. The reaction of T 2 and N 2 to form NT 3 is a slow process, particularly when the tritium concentration is low. The reaction requires weeks or months to reach radiochemical equilibrium dependent on the concentrations of the reactants. 4 refs., 6 figs., 1 tab

  15. Galaxy formation and evolution

    CERN Document Server

    Mo, Houjun; White, Simon

    2010-01-01

    The rapidly expanding field of galaxy formation lies at the interface between astronomy, particle physics, and cosmology. Covering diverse topics from these disciplines, all of which are needed to understand how galaxies form and evolve, this book is ideal for researchers entering the field. Individual chapters explore the evolution of the Universe as a whole and its particle and radiation content; linear and nonlinear growth of cosmic structure; processes affecting the gaseous and dark matter components of galaxies and their stellar populations; the formation of spiral and elliptical galaxies; central supermassive black holes and the activity associated with them; galaxy interactions; and the intergalactic medium. Emphasizing both observational and theoretical aspects, this book provides a coherent introduction for astronomers, cosmologists, and astroparticle physicists to the broad range of science underlying the formation and evolution of galaxies.

  16. Observsational Planet Formation

    Science.gov (United States)

    Dong, Ruobing; Zhu, Zhaohuan; Fung, Jeffrey

    2017-06-01

    Planets form in gaseous protoplanetary disks surrounding newborn stars. As such, the most direct way to learn how they form from observations, is to directly watch them forming in disks. In the past, this was very difficult due to a lack of observational capabilities; as such, planet formation was largely a subject of pure theoretical astrophysics. Now, thanks to a fleet of new instruments with unprecedented resolving power that have come online recently, we have just started to unveil features in resolve images of protoplanetary disks, such as gaps and spiral arms, that are most likely associated with embedded (unseen) planets. By comparing observations with theoretical models of planet-disk interactions, the masses and orbits of these still forming planets may be constrained. Such planets may help us to directly test various planet formation models. This marks the onset of a new field — observational planet formation. I will introduce the current status of this field.

  17. Forces in strategy formation

    DEFF Research Database (Denmark)

    Steensen, Elmer Fly; Sanchez, Ron

    2008-01-01

    This chapter proposes that organizational strategy formation should be characterized theoretically as a process that is subject to several interacting forces, rather than represented by separate discrete decisionmodels or theoretic perspectives, as is commonly done in the strategic management...... literature. Based on an extensive review of relevant theory and empirical work in strategic decision-making, organizational change theory, cognitive and social psychology, and strategy processes, seven kinds of ''forces'' - rational, imposed, teleological, learning, political, heuristic, and social...... - are identified as interacting in and having significant influence on the strategy formation process. It is further argued that by applying a holistic ''forces-view'' of the significant and interacting influences on strategy formation, we can better understand the dynamics and challenges in managing the process...

  18. Planetesimals and Planet Formation

    Science.gov (United States)

    Chambers, John

    The first step in the standard model for planet formation is the growth of gravitationally bound bodies called ``planetesimals'' from dust grains in a protoplanetary disk. Currently, we do not know how planetesimals form, how long they take to form, or what their sizes and mechanical properties are. The goal of this proposal is to assess how these uncertainties affect subsequent stages of planetary growth and the kind of planetary systems that form. The work will address three particular questions: (i) Can the properties of small body populations in the modern Solar System constrain the properties of planetesimals? (ii) How do the properties of planetesimals affect the formation of giant planets? (iii) How does the presence of a water ice condensation front (the ``snow line'') in a disk affect planetesimal formation and the later stages of planetary growth? These questions will be examined with computer simulations of planet formation using new computer codes to be developed as part of the proposal. The first question will be addressed using a statistical model for planetesimal coagulation and fragmentation. This code will be merged with the proposer's Mercury N-body integrator code to model the dynamics of large protoplanets in order to address the second question. Finally, a self- consistent model of disk evolution and the radial transport of water ice and vapour will be added to examine the third question. A theoretical understanding of how planets form is one of the key goals of NASA and the Origins of Solar Systems programme. Researchers have carried out many studies designed to address this goal, but the questions of how planetesimals form and how their properties affect planet formation have received relatively little attention. The proposed work will help address these unsolved questions, and place other research in context by assessing the importance of planetesimal origins and properties for planet formation.

  19. Superclusters and galaxy formation

    International Nuclear Information System (INIS)

    Einasto, J.; Joeveer, M.; Saar, E.

    1979-01-01

    The spatial distribution of Galaxies and Galaxy congestions in the southern galactic hemisphere is studied. The rich galaxy congestions, containing many elliptic Galaxies and radiogalaxies, are linked with each other by chains of scanty congestions with moderate content of elliptic Galaxies and radiogalaxies. The flat formation, linking the density pikes and the intermediate chains, can reasonably be called supercongestion. In the central region of supercongestions there is a thin layer of Galaxies consisting of only spiral Galaxies. The neighbouring supercongestions touch each other, while the intersupercongestion space contains no Galaxy congestions and almost no Galaxies. It is shown that such a structure was, apparently, formed before the formation of Galaxies

  20. Formation of galaxies

    International Nuclear Information System (INIS)

    Szalay, A.S.

    1984-12-01

    The present theories of galaxy formation are reviewed. The relation between peculiar velocities and the correlation function of galaxies points to the possibility that galaxies do not form uniformly everywhere. Scale invariant properties of the cluster-cluster correlations are discussed. Comparing the correlation functions in a dimensionless way, galaxies appear to be stronger clustered, in contrast with the comparison of the dimensional amplitudes of the correlation functions. Theoretical implications of several observations as Lyman-α clouds, correlations of faint galaxies are discussed. None of the present theories of galaxy formation can account for all facts in a natural way. 29 references

  1. The formation of stars

    CERN Document Server

    Stahler, Steven W

    2008-01-01

    This book is a comprehensive treatment of star formation, one of the most active fields of modern astronomy. The reader is guided through the subject in a logically compelling manner. Starting from a general description of stars and interstellar clouds, the authors delineate the earliest phases of stellar evolution. They discuss formation activity not only in the Milky Way, but also in other galaxies, both now and in the remote past. Theory and observation are thoroughly integrated, with the aid of numerous figures and images. In summary, this volume is an invaluable resource, both as a text f

  2. Densities and Kinematic Viscosities for the Systems Benzene + Methyl Formate, Benzene + Ethyl Formate, Benzene + Propyl Formate, and Benzene + Butyl Formate

    DEFF Research Database (Denmark)

    Emmerling, Uwe; Rasmussen, Peter

    1998-01-01

    a Redlich-Kister type of expression with temperature-independent parameters and the data for the systems benzene + ethyl formate, benzene + propyl formate, and benzene + butyl formate with temperature-dependent parameters. The viscosities have furthermore been compared to values predicted by means of the GC......Densities and kinematic viscosities have been measured for the system benzene + methyl formate at 20°C and for the systems benzene + ethyl formate, benzene + propyl formate, and benzene + butyl formate from 20°C to 50°C. The results for the system benzene + methyl formate have been correlated using...

  3. Barrier cell sheath formation

    International Nuclear Information System (INIS)

    Kesner, J.

    1980-04-01

    The solution for electrostatic potential within a simply modeled tandem mirror thermal barrier is seen to exhibit a sheath at each edge of the cell. The formation of the sheath requires ion collisionality and the analysis assmes that the collisional trapping rate into the barrier is considerably slower than the barrier pump rate

  4. Formation of topological defects

    International Nuclear Information System (INIS)

    Vachaspati, T.

    1991-01-01

    We consider the formation of point and line topological defects (monopoles and strings) from a general point of view by allowing the probability of formation of a defect to vary. To investigate the statistical properties of the defects at formation we give qualitative arguments that are independent of any particular model in which such defects occur. These arguments are substantiated by numerical results in the case of strings and for monopoles in two dimensions. We find that the network of strings at formation undergoes a transition at a certain critical density below which there are no infinite strings and the closed-string (loop) distribution is exponentially suppressed at large lengths. The results are contrasted with the results of statistical arguments applied to a box of strings in dynamical equilibrium. We argue that if point defects were to form with smaller probability, the distance between monopoles and antimonopoles would decrease while the monopole-to-monopole distance would increase. We find that monopoles are always paired with antimonopoles but the pairing becomes clean only when the number density of defects is small. A similar reasoning would also apply to other defects

  5. The formation of galaxies

    International Nuclear Information System (INIS)

    Gunn, J.E.

    1983-01-01

    The presently fashionable ideas for galaxy formation are reviewed briefly, and it is concluded that the standard isothermal heirarchy fits the available data best. A simple infall picture is presented which explains many of the observed properties of disk galaxies. (orig.)

  6. Reconsidering Formative Measurement

    Science.gov (United States)

    Howell, Roy D.; Breivik, Einar; Wilcox, James B.

    2007-01-01

    The relationship between observable responses and the latent constructs they are purported to measure has received considerable attention recently, with particular focus on what has become known as formative measurement. This alternative to reflective measurement in the area of theory-testing research is examined in the context of the potential…

  7. Chlorination and chloramines formation

    International Nuclear Information System (INIS)

    Yee, Lim Fang; Mohd Pauzi Abdullah; Sadia Ata; Abbas Abdullah; Basar IShak; Khairul Nidzham

    2008-01-01

    Chlorination is the most important method of disinfection in Malaysia which aims at ensuring an acceptable and safe drinking water quality. The dosing of chlorine to surface water containing ammonia and nitrogen compounds may form chloramines in the treated water. During this reaction, inorganic and organic chloramines are formed. The recommended maximum acceptable concentration (MAC) for chloramines in drinking water is 3000 μg/L. The production of monochloramine, dichloramine and trichloramine is highly dependent upon pH, contact time and the chlorine to ammonia molar ratio. The purpose of this study is to examine the formation of chloramines that occur upon the chlorination during the treatment process. Chloramines were determined using the N,N-diethyl-p-phenylenediamine (DPD) colorimetric method. The influences of ammonia, pH and chlorine dosage on the chloramines formation were also studied. This paper presents a modeling approach based on regression analysis which is designed to estimate the formation of chloramines. The correlation between the concentration of chloramines and the ammonia, pH and chlorine dosage was examined. In all cases, the quantity of chloramines formed depended linearly upon the amount of chlorine dosage. On the basis of this study it reveals that the concentration of chloramines is a function of chlorine dosage and the ammonia concentration to the chlorination process. PH seems to not significantly affect the formation of chloramines. (author)

  8. Temperature controlled 'void' formation

    International Nuclear Information System (INIS)

    Dasgupta, P.; Sharma, B.D.

    1975-01-01

    The nucleation and growth of voids in structural materials during high temperature deformation or irradiation is essentially dependent upon the existence of 'vacancy supersaturation'. The role of temperature dependent diffusion processes in 'void' formation under varying conditions, and the mechanical property changes associated with this microstructure are briefly reviewed. (author)

  9. Triggered star formation

    Czech Academy of Sciences Publication Activity Database

    Palouš, Jan; Ehlerová, Soňa

    2002-01-01

    Roč. 12, - (2002), s. 35-36 ISSN 1405-2059 R&D Projects: GA AV ČR IAA3003705; GA AV ČR KSK1048102 Institutional research plan: CEZ:AV0Z1003909 Keywords : interstellar medium * star formation * HI shells Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  10. Syntactic Formats for Free

    DEFF Research Database (Denmark)

    Klin, Bartek; Sobocinski, Pawel

    2003-01-01

    A framework of Plotkin and Turi’s, originally aimed at providing an abstract notion of bi-simulation, is modified to cover other operational equivalences and preorders. Combined with bi-algebraic methods, it yields a technique for the derivation of syntactic formats for transition system specific...

  11. Formation of double layers

    International Nuclear Information System (INIS)

    Leung, P.; Wong, A.Y.; Quon, B.H.

    1981-01-01

    Experiments on both stationary and propagating double layers and a related analytical model are described. Stationary double layers were produced in a multiple plasma device, in which an electron drift current was present. An investigation of the plasma parameters for the stable double layer condition is described. The particle distribution in the stable double layer establishes a potential profile, which creates electron and ion beams that excite plasma instabilities. The measured characteristics of the instabilities are consistent with the existence of the double layer. Propagating double layers are formed when the initial electron drift current is large. Ths slopes of the transition region increase as they propagate. A physical model for the formation of a double layer in the experimental device is described. This model explains the formation of the low potential region on the basis of the space charge. This space charge is created by the electron drift current. The model also accounts for the role of ions in double layer formation and explains the formation of moving double layers. (Auth.)

  12. COMPETENCYTHE FORMATION FOR LIFE

    Directory of Open Access Journals (Sweden)

    Milagros Mederos-Piñeiro

    2016-07-01

    Full Text Available The formation of life competences is the result of a quality education that prepares students to meet the challenges of a fast moving world where equality and equal opportunities should constitute premises of education; training them is a challenge teachers to assume new generations contribute actively to a better world. In Cuba are important research on the formation of communication competences and self-regulated learning in primary school. The paper shows the result of an investigation that provides a methodology for the formation of life competences in primary school education, used as an essential pathway research activity. The methodological approach of research has a quantitative approach and an explanatory scope to establish and make sense of understanding the causal relationship between the direction of research activity and training of life competences. Theoretical, empirical and mathematical-statistical, for characterizing the initial state, processing of results and analysis: research methods are used. The application of the methodology for the formation of life competences makes teachers lead the teaching-learning process with a research and transforming teaching concept, where the school is the protagonist of their learning and causes changes in their performances, which are evident in the formed competences related to effective and affective communication; the solution of problems related to life; the use of means in obtaining the knowledge and the expression of a behavior consistent with school and social demands. The effectiveness of the methodology confirms that there is a causal relationship between the direction of research activity by teachers and the formation of life competences in school.

  13. Medusae Fossae Formation

    Science.gov (United States)

    2002-01-01

    (Released 10 April 2002) The Science This THEMIS visible image was acquired near 7o S, 172o W (188o E) and shows a remarkable martian geologic deposit known as the Medusae Fossae Formation. This Formation, seen here as the raised plateau in the upper two-thirds of the image, is a soft, easily eroded deposit that extends for nearly 1,000 km along the equator of Mars. In this region the deposit has been heavily eroded by the wind to produce a series of linear ridges called yardangs. These parallel ridges point in direction of the prevailing winds that carved them, and demonstrate the power of martian winds to sculpt the dry landscape of Mars. The Medusae Fossae Formation has been completely stripped from the surface in the lower third of the image, revealing a harder layer below that is more resistant to wind erosion. The easily eroded nature of the Medusae Fossae Formation suggests that it is composed of weakly cemented particles, and was most likely formed by the deposition of wind-blown dust or volcanic ash. Several ancient craters that were once completely buried by this deposit are being exposed, or exhumed, as the overlying Medusae Formation is removed. Very few impact craters are visible on this Formation, indicating that the surface seen today is relatively young, and that the processes of erosion are likely to be actively occurring. The Story Medusa of Greek mythology fame, the name-giver to this region, had snaky locks of hair that could turn a person to stone. Wild and unruly, this monster of the underworld could certainly wreak havoc on the world of the human imagination. As scary as she was, Medusa would have no advantage over the fierce, masterful winds blowing across Mars, which once carved the streaky, terrain at the top of this image. Wild and whipping, these winds have slowly eroded away the 'topsoil,' revealing ancient craters and other surface features they once covered. The loosely cemented particles of this 'topsoil' are likely made up of dust

  14. The format of things

    DEFF Research Database (Denmark)

    Jørnø, Rasmus Leth

    this conception is identified as “the Format of Things.” The format is embedded in our everyday thinking. In relation to design,it is found in the name taken by the design community, that is human-computer interaction (HCI), and it is mirrored in the desktop metaphor, wherein information is conceived...... available. It consists of philosophical considerations on matters of relevance for the design of interfaces. It takes the position that the graphical user interfaces of computers (the Desktop Metaphor or Windows, Icons, Menus, Pointers [‘WIMP’]) that ordinarily come to mind for most people are cognates......The development of novel interfaces is one of the most important current design challenges for the intellectual, cultural and cognitive evolution of human imagination and knowledge work. Unfortunately, the thinking surrounding this design challenge is heavily mired in conceptions that harbor...

  15. Plasma formation in TBR

    International Nuclear Information System (INIS)

    Del Bosco, E.

    1981-01-01

    In this work are presented and discussed results of the formation and equilibrium of the plasma current in TBR, a small tokamak, designed and contructed at the Instituto de Fisica of Universidade de Sao Paulo. The measured breakdown curves for H 2 , A and He are compared with the predictions of a simple model with reasonable agreement. The influence of stray magnetic fields in the plasma formation is investigated and conditions are chosen to facilitate the breakdown. The time profile of loop voltage and plasma current for shots with plasma equilibrium are shown. A comparison is made between experimental results and analytical-numerical model for tokamaks discharges with ohmic heating. Reasonable agreement is obtained when Z, effective atomic number, is assumed as a parameter. (Author) [pt

  16. Formation of coronal cavities

    International Nuclear Information System (INIS)

    An, C.H.; Suess, S.T.; Tandberg-Hanssen, E.; Steinolfson, R.S.

    1986-01-01

    A theoretical study of the formation of a coronal cavity and its relation to a quiescent prominence is presented. It is argued that the formation of a cavity is initiated by the condensation of plasma which is trapped by the coronal magnetic field in a closed streamer and which then flows down to the chromosphere along the field lines due to lack of stable magnetic support against gravity. The existence of a coronal cavity depends on the coronal magnetic field strength; with low strength, the plasma density is not high enough for condensation to occur. Furthermore, we suggest that prominence and cavity material is supplied from the chromospheric level. Whether a coronal cavity and a prominence coexist depends on the magnetic field configuration; a prominence requires stable magnetic support

  17. Understanding Alliance Formation Patterns

    Science.gov (United States)

    2015-12-01

    military, transportation, and communications technologies, which caused every place in the world to be politically significant. Second, “divisions of power...test a similar claim about the association between distance and dyadic alliance formation. In their first model, in which they use the complete data...1885 to 1990] are positively related to dyadic trade levels, and that their non- defense-pact counterparts are not significantly related to trade in

  18. Alkali metal hydride formation

    International Nuclear Information System (INIS)

    1976-01-01

    The present invention relates to a method of producing alkali metal hydrides by absorbing hydrogen gas under pressure into a mixture of lower alkyl mono amines and alkali metal alkyl amides selected from sodium and potassium amides formed from said amines. The present invention also includes purification of a mixture of the amines and amides which contain impurities, such as is used as a catalytic exchange liquid in the enrichment of deuterium, involving the formation of the alkali metal hydride

  19. Formation of TRAPPIST-1

    Science.gov (United States)

    Ormel, C. W.; Liu, B.; Schoonenberg, D.

    2017-09-01

    We present a model for the formation of the recently-discovered TRAPPIST-1 planetary system. In our scenario planets form in the interior regions, by accretion of mm to cm-size particles (pebbles) that drifted from the outer disk. This scenario has several advantages: it connects to the observation that disks are made up of pebbles, it is efficient, it explains why the TRAPPIST-1 planets are ˜Earth mass, and it provides a rationale for the system's architecture.

  20. THE ALLIANCE FORMATION PROCESS

    OpenAIRE

    Whipple, Judith M.; Frankel, Robert

    1998-01-01

    While interest in developing strategic alliances within the food system continues to increase, there remains considerable risk when firms adopt such a cooperative strategy. The risk is due in part to the lack of concrete guidelines that illustrate the steps or stages of alliance development and the important strategic and operational decisions required at each stage. The existence of such guidelines would facilitate alliance formation and enable managers and researchers to better understand a...

  1. Complexity and formative experiences

    Directory of Open Access Journals (Sweden)

    Roque Strieder

    2017-12-01

    Full Text Available The contemporaneity is characterized by instability and diversity calling into question certainties and truths proposed in modernity. We recognize that the reality of things and phenomena become effective as a set of events, interactions, retroactions and chances. This different frame extends the need for revision of the epistemological foundations that sustain educational practices and give them sense. The complex thinking is an alternative option for acting as a counterpoint to classical science and its reductionist logic and knowledge compartmentalization, as well as to answer to contemporary epistemological and educational challenges. It aims to associate different areas and forms of knowledge, without, however merge them, distinguishing without separating the several disciplines and instances of the realities. This study, in theoretical references, highlights the relevance of complex approaches to support formative experiences because also able to produce complexities in reflections about educational issues. We conclude that formative possibilities from complexity potentialize the resignification of human’s conception and the understanding of its singularity in interdependence; The understanding that pedagogical and educational activities is a constant interrogation about the possibilities of knowing the knowledge and reframe learning, far beyond knowing its functions and utilitarian purposes; and, as a formative possibility, places us on the trail of responsibility, not as something eventual, but present and indicative of freedom to choose to stay or go beyond.

  2. Terrestrial planet formation.

    Science.gov (United States)

    Righter, K; O'Brien, D P

    2011-11-29

    Advances in our understanding of terrestrial planet formation have come from a multidisciplinary approach. Studies of the ages and compositions of primitive meteorites with compositions similar to the Sun have helped to constrain the nature of the building blocks of planets. This information helps to guide numerical models for the three stages of planet formation from dust to planetesimals (~10(6) y), followed by planetesimals to embryos (lunar to Mars-sized objects; few 10(6) y), and finally embryos to planets (10(7)-10(8) y). Defining the role of turbulence in the early nebula is a key to understanding the growth of solids larger than meter size. The initiation of runaway growth of embryos from planetesimals ultimately leads to the growth of large terrestrial planets via large impacts. Dynamical models can produce inner Solar System configurations that closely resemble our Solar System, especially when the orbital effects of large planets (Jupiter and Saturn) and damping mechanisms, such as gas drag, are included. Experimental studies of terrestrial planet interiors provide additional constraints on the conditions of differentiation and, therefore, origin. A more complete understanding of terrestrial planet formation might be possible via a combination of chemical and physical modeling, as well as obtaining samples and new geophysical data from other planets (Venus, Mars, or Mercury) and asteroids.

  3. Fracturing of subterranean formations

    Energy Technology Data Exchange (ETDEWEB)

    Kiel, O.M.; Kidwell, A.L.

    1968-03-19

    This method of propping fractured formations results in high conductivities. In the method, certain naturally occurring crystals are used as propping agents. Suitable crystals include garnet, corundum, zircon, rutile, high-temperature quartz, and other minerals which have Moh's hardness values of about 6 or greater and weather out as individual crystals of about 40 mesh or larger. These are said to result in permeabilities significantly higher than those obtained with ordinary quartz sand, metallic shot, glass beads, plastic particles, walnut hulls, or similar materials. (10 claims)

  4. Situated Formative Feedback

    DEFF Research Database (Denmark)

    Lukassen, Niels Bech; Wahl, Christian; Sorensen, Elsebeth Korsgaard

    refer to this type of feedback as, Situated Formative Feedback (SFF). As a basis for exploring, identifying and discussing relevant aspects of SFF the paper analyses qualitative data from a Moodle dialogue. Data are embedded in the qualitative analytic program Nvivo and are analysed with a system...... theoretical textual analysis method. Asynchronous written dialogue from an online master’s course at Aalborg University forms the empirical basis of the study. The findings suggests in general that students play an essential role in SFF and that students and educators are equal in the COP, but holds different...

  5. Superclusters and galaxy formation

    Energy Technology Data Exchange (ETDEWEB)

    Einasto, J; Joeveer, M; Saar, E [Tartu Astrophysical Observatory, Toravere, Estonia (USSR)

    1980-01-03

    A study of the structure of superclusters in the Southern galactic hemisphere using Zwicky clusters as principal tracers of the large-scale structure of the Universe is reported. The data presented suggest that the formation of galaxies was a two stage process involving larger spatial dimensions than earlier workers have postulated. In the first stage proto-superclusters and big holes had to form from the non-dissipative dark matter while in the second hot gas, by cooling and settling down into the potential wells caused by dark matter, will form galaxies and clusters of galaxies.

  6. Urbanization and Slum Formation

    Science.gov (United States)

    Phua, Kai Hong

    2007-01-01

    The formation of slums need not be inevitable with rapid urbanization. Such an argument appears to be contradicted by evidence of large slum populations in a large number of developing countries and particularly in rapidly urbanizing regions like Asia. The evidence discussed suggests that city authorities faced with rapid urban development lack the capacity to cope with the diverse demands for infrastructural provision to meet economic and social needs. Not only are strategic planning and intervention major issues in agenda to manage rapid urbanization, but city governments are not effectively linking the economic development trajectory to implications for urban growth and, hence, housing needs. In the following discussion, a case study is presented in support of the argument that city governments have to first recognize and then act to establish the link that is crucial between economic development, urban growth, and housing. This is the agendum that has been largely neglected by city and national governments that have been narrowly focused on economic growth with the consequent proliferation of slum formation as a housing solution. PMID:17387618

  7. Formation of planetary systems

    International Nuclear Information System (INIS)

    Brahic, A.

    1982-01-01

    It seemed appropriate to devote the 1980 School to the origin of the solar system and more particularly to the formation of planetary systems (dynamic accretion processes, small bodies, planetary rings, etc...) and to the physics and chemistry of planetary interiors, surface and atmospheres (physical and chemical constraints associated with their formation). This Summer School enabled both young researchers and hard-nosed scientists, gathered together in idyllic surroundings, to hold numerous discussions, to lay the foundations for future cooperation, to acquire an excellent basic understanding, and to make many useful contacts. This volume reflects the lectures and presentations that were delivered in this Summer School setting. It is aimed at both advanced students and research workers wishing to specialize in planetology. Every effort has been made to give an overview of the basic knowledge required in order to gain a better understanding of the origin of the solar system. Each article has been revised by one or two referees whom I would like to thank for their assistance. Between the end of the School in August 1980 and the publication of this volume in 1982, the Voyager probes have returned a wealth of useful information. Some preliminary results have been included for completeness

  8. A Mesoproterozoic iron formation

    Science.gov (United States)

    Canfield, Donald E.; Zhang, Shuichang; Wang, Huajian; Wang, Xiaomei; Zhao, Wenzhi; Su, Jin; Bjerrum, Christian J.; Haxen, Emma R.; Hammarlund, Emma U.

    2018-04-01

    We describe a 1,400 million-year old (Ma) iron formation (IF) from the Xiamaling Formation of the North China Craton. We estimate this IF to have contained at least 520 gigatons of authigenic Fe, comparable in size to many IFs of the Paleoproterozoic Era (2,500–1,600 Ma). Therefore, substantial IFs formed in the time window between 1,800 and 800 Ma, where they are generally believed to have been absent. The Xiamaling IF is of exceptionally low thermal maturity, allowing the preservation of organic biomarkers and an unprecedented view of iron-cycle dynamics during IF emplacement. We identify tetramethyl aryl isoprenoid (TMAI) biomarkers linked to anoxygenic photosynthetic bacteria and thus phototrophic Fe oxidation. Although we cannot rule out other pathways of Fe oxidation, iron and organic matter likely deposited to the sediment in a ratio similar to that expected for anoxygenic photosynthesis. Fe reduction was likely a dominant and efficient pathway of organic matter mineralization, as indicated by organic matter maturation by Rock Eval pyrolysis combined with carbon isotope analyses: Indeed, Fe reduction was seemingly as efficient as oxic respiration. Overall, this Mesoproterozoic-aged IF shows many similarities to Archean-aged (>2,500 Ma) banded IFs (BIFs), but with an exceptional state of preservation, allowing an unprecedented exploration of Fe-cycle dynamics in IF deposition.

  9. Endocytosis and Enamel Formation

    Directory of Open Access Journals (Sweden)

    Cong-Dat Pham

    2017-07-01

    Full Text Available Enamel formation requires consecutive stages of development to achieve its characteristic extreme mineral hardness. Mineralization depends on the initial presence then removal of degraded enamel proteins from the matrix via endocytosis. The ameloblast membrane resides at the interface between matrix and cell. Enamel formation is controlled by ameloblasts that produce enamel in stages to build the enamel layer (secretory stage and to reach final mineralization (maturation stage. Each stage has specific functional requirements for the ameloblasts. Ameloblasts adopt different cell morphologies during each stage. Protein trafficking including the secretion and endocytosis of enamel proteins is a fundamental task in ameloblasts. The sites of internalization of enamel proteins on the ameloblast membrane are specific for every stage. In this review, an overview of endocytosis and trafficking of vesicles in ameloblasts is presented. The pathways for internalization and routing of vesicles are described. Endocytosis is proposed as a mechanism to remove debris of degraded enamel protein and to obtain feedback from the matrix on the status of the maturing enamel.

  10. Star Formation in Irregular Galaxies.

    Science.gov (United States)

    Hunter, Deidre; Wolff, Sidney

    1985-01-01

    Examines mechanisms of how stars are formed in irregular galaxies. Formation in giant irregular galaxies, formation in dwarf irregular galaxies, and comparisons with larger star-forming regions found in spiral galaxies are considered separately. (JN)

  11. Standard exercise report format (SERF)

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    This talk summarizes the reasons for the development of draft SERF the Standard Exercise Report Format used for reporting the results of emergency preparedness exercises, and gives a summary of the format and rational behind it

  12. Sacrococcygeal teratoma: 10-year experience in upper Egypt

    African Journals Online (AJOL)

    time of surgical approach, histopathology, recurrences, bladder and anorectal function, and cosmetic outcome. Results Forty-five patients with SCT were referred to the. Pediatric Surgical Unit. The time of referral was as follows: immediately after birth in ... is from pluripotent cells in Hensen's node of primitive streak, and they ...

  13. The incidence of associated abnormalities in patients with sacrococcygeal teratoma.

    Science.gov (United States)

    Kremer, Marijke E B; Althof, Jessica F; Derikx, Joep P M; van Baren, Robertine; Heij, Hugo A; Wijnen, Marc H W A; Wijnen, René M H; van der Zee, David C; van Heurn, L W Ernest

    2018-01-31

    Gross genetic causes for SCT are unknown; however, it might be associated with other abnormalities. We assessed the incidence of associated abnormalities in a large national cohort of neonates with SCT and aimed to identify predictive risk factors. The medical records were reviewed of 235 consecutive neonates with SCT treated at the six pediatric surgical centers in the Netherlands from 1970 to 2010. Potential risk factors for associated abnormalities analyzed included sex, gestational age, tumor-volume/histology and Altman-classification. In 76 patients (32.3%) at least one associated abnormality was diagnosed, with hydronephrosis as the most common (16.2%) and hip dysplasia in 4.3%. Multiple abnormalities were documented for 21 (9.0%). Prematurity and Altman type IV SCT were associated with an increased risk of any associated abnormality. No association between increased tumor-volume and hydronephrosis or hip dysplasia was found. Patients with type IV Altman SCT had a fourfold risk of suffering from hydronephrosis compared to Altman type I SCT. SCT was associated with other abnormalities in one-third of children. Some were tumor-related while others were related to prematurity or occurred sporadically. In contrast to clinically obvious anomalies, hip dysplasia or hydronephrosis might be latently present with more subtle clinical presentation. We therefore suggest renal- and hip-ultrasound in all patients, certainly those with Altman type IV SCT. Level II (retrospective study). Copyright © 2018. Published by Elsevier Inc.

  14. Sacrococcygeal teratoma excision: a vertical rather than transverse ...

    African Journals Online (AJOL)

    2017-04-07

    Apr 7, 2017 ... baby itself. However, contrary to what the term implies, most cases of SCT were shown to have a favorable surgical outcome [3,6,7]. One exception is the presence ... postoperatively showing wound disruption; (g) healing by secondary intention resulting in a satisfactory hidden scar at 6-month follow-up.

  15. The incidence of associated abnormalities in patients with sacrococcygeal teratoma

    NARCIS (Netherlands)

    Kremer, Marijke E. B.; Althof, Jessica F.; Derikx, Joep P. M.; van Baren, Robertine; Heij, Hugo A.; Wijnen, Marc H. W. A.; Wijnen, René M. H.; van der Zee, David C.; van Heurn, L. W. Ernest

    2018-01-01

    Gross genetic causes for SCT are unknown; however, it might be associated with other abnormalities. We assessed the incidence of associated abnormalities in a large national cohort of neonates with SCT and aimed to identify predictive risk factors. The medical records were reviewed of 235

  16. Neonatal Airway Obstruction from an Immature Teratoma: The ...

    African Journals Online (AJOL)

    1) Table of Contents (TOC) email alert. Receive an email alert containing the TOC when a new complete issue of the journal is made available online. To register for TOC alerts go to www.amhsr.org/signup.asp. 2) RSS feeds. Really Simple Syndication (RSS) helps you to get alerts on new publication right on your desktop ...

  17. Squamous Cell Carcinoma Arising in a Testicular Teratoma and ...

    African Journals Online (AJOL)

    Journal of Surgical Technique and Case Report | Jul-Dec 2011 | Vol-3 | Issue-2. 99. Khan and Bagchi: ... pain and anorexia for last two months and a painless umbilical nodule of .... A clinicopathologic study of 11 cases. Cancer 1984 ...

  18. Sacrococcygeal teratoma: Clinical characteristics and long-term ...

    African Journals Online (AJOL)

    2009-10-05

    Oct 5, 2009 ... chemotherapy, while two were well at 12 and 24 months after surgical excision and chemotherapy. Even though our patients with malignant disease were few, it would appear that they do well after chemotherapy and excision as noted by Wakhlu et al.[8]. A number of reports have attempted to assess long-.

  19. Primary retroperitoneal teratomas in children: A single institution ...

    African Journals Online (AJOL)

    But in one patient injury to inferior vena cava (IVC) occurred which was repaired successfully. Majority (7 out of 8) were histological benign, and in one yolk sac tumour was malignant component which needed chemotherapy. All children were on followup and one patient with malignancy lost to follow-up after three cycles of ...

  20. Restoring formation after leaching process

    International Nuclear Information System (INIS)

    Barrett, R.B.

    1983-01-01

    A method of restoring a formation which had uranium and other mineral values extracted by an alkaline lixiviant comprises introducing a source of phosphate in an amount sufficient to lower the level of soluble uranium compounds below that previously existing in the formation by the formation of insoluble uranium phosphate compounds

  1. Formative Research in Educational Media.

    Science.gov (United States)

    Hodapp, Timothy

    This paper distinguishes between basic research, applied research, and evaluation. Evaluation is broken down into two types: summative and formative. The limitations of formative research are presented, followed by a discussion of the value of the formative researcher participating in the product planning process. The types of data which formative…

  2. Designing for informed group formation

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh; Juel Jacobsen, Alice; Riis, Marianne

    2012-01-01

    A new design ―project preparation‖ preparing for the group formation in problem based project work is proposed and investigated. The main problem is to overcome group formation based on existing relations. The hypothesis is that theme development and group formation are somewhat counterproductive...

  3. Determinants for gallstone formation

    DEFF Research Database (Denmark)

    Shabanzadeh, Daniel Monsted; Sorensen, Lars Tue; Jørgensen, Torben

    2016-01-01

    . Gallstone incidence was assessed through repeated ultrasound examinations. Body mass index (BMI), blood pressure, self-rated health, lifestyle variables, blood lipids, and use of female sex hormones were measured at the baseline examination. Statistical analyses included logistic regression. Based...... re-examination were followed-up completely (mean 11.6 years, N = 2848). The overall cumulative incidence of gallstones was 0.60% per year. Independent positive determinants for incident gallstones were age, female sex, non-high density lipoprotein (non-HDL) cholesterol, and gallbladder polyps...... associations were found for blood pressure, smoking, alcohol consumption, HDL cholesterol, or triglycerides in meta-analyses. Conclusions: Age, female sex, BMI, non-HDL cholesterol, and polyps are independent determinants for gallstone formation. Incident gallstones and the metabolic syndrome share common risk...

  4. Standardizing exchange formats

    International Nuclear Information System (INIS)

    Lemmel, H.D.; Schmidt, J.J.

    1992-01-01

    An international network of co-operating data centres is described who maintain identical data bases which are simultaneously updated by an agreed data exchange procedure. The agreement covers ''data exchange formats'' which are compatible to the centres' internal data storage and retrieval systems which remain different, optimized at each centre to the available computer facilities and to the needs of the data users. Essential condition for the data exchange is an agreement on common procedures for the data exchange is an agreement on common procedures for the data compilation, including critical data analysis and validation. The systems described (''EXFOR'', ''ENDF'', ''CINDA'') are used for ''nuclear reaction data'', but the principles used for data compilation and exchange should be valid also for other data types. (author). 24 refs, 4 figs

  5. Recipes for planet formation

    Science.gov (United States)

    Meyer, Michael R.

    2009-11-01

    Anyone who has ever used baking soda instead of baking powder when trying to make a cake knows a simple truth: ingredients matter. The same is true for planet formation. Planets are made from the materials that coalesce in a rotating disk around young stars - essentially the "leftovers" from when the stars themselves formed through the gravitational collapse of rotating clouds of gas and dust. The planet-making disk should therefore initially have the same gas-to-dust ratio as the interstellar medium: about 100 to 1, by mass. Similarly, it seems logical that the elemental composition of the disk should match that of the star, reflecting the initial conditions at that particular spot in the galaxy.

  6. Formation of Service Ecosystems

    DEFF Research Database (Denmark)

    Jonas, Julia M.; Sörhammar, David; Satzger, Gerhard

    – i.e. the “birth phase” (Moore, 2009) of a service ecosystem. This paper, therefore, aims to explore how the somewhat “magic” processes of service ecosystem formation that are being taken for granted actually occur. Methodology/Approach: Building on a review of core elements in the definitions...... for Harvard students) or value proposition (share messages, photos, videos, etc. with friends). Processes of configuring actors, resources, and value propositions are influenced by the structural embeddedness of the service ecosystem (e.g., regional infrastructure, existing networks of actors, or resource...... availability) as well as guided by the actors’ own and shared institutions (e.g., rules, norms,and beliefs).We contextualize each starting point with illustrative cases and analyze the service ecosystem configuration process: “Axoon/Trumpf” (initiated by resources), “JOSEPHS – the service manufactory...

  7. Symbol Formation Reconsidered

    DEFF Research Database (Denmark)

    Wagoner, Brady

    2013-01-01

    them vis-à-vis other research at Clark and in American psychology more generally. The second two articles analyse Werner and Kaplan’s notions of ‘distancing’ and ‘physiognomic metaphor’, showing their roots in naturphilosophie and comparing them with contemporary theories. The last four articles apply......Werner and Kaplan’s Symbol formation was published 50 years ago but its insights have yet to be adequately explored by psychology and other social sciences. This special issue aims to revisit this seminal work in search of concepts to work on key issues facing us today. This introductory article...... begins with a brief outline and contextualization of the book as well as of the articles that this special issue comprises. The first two articles were written by contributors who were part of the Werner era at Clark University. They explore the key concepts of the organismic and development, and situate...

  8. Germinomas cerebrais (teratomas atípicos da pineal Cerebral germinomas (atipical teratomas of the pineal region

    Directory of Open Access Journals (Sweden)

    Alexandre Alencar

    1981-12-01

    Full Text Available São estudados três casos de germinomas cerebrais, sendo um tópico, da região pineal, e dois ectópicos, chamados germinomas supra-selares ou quiasmáticos. Estes últimos parecem ser mais agressivos que os seus congeneres tópicos, pois alem de se disseminarem pelas cisternas basais, costumam infiltrar as paredes do III ventrículo, fórnix, hipotálamo, nervos e quiasma ópticos. Caracteristicamente produzem um enorme aumento das proteínas liquóricas, desacompanhado de uma pleocitose proporcional. As proteínas liquóricas aumentadas sao globulinas cujas reações mostram-se fortemente positivas, possivelmente produzidas pelas celulas de aspecto linfocitario que constituem parte desta neoplasia. O aumento das proteinas liquoricas e tao acentuado que em presenca de uma crianca ou adolescente com sindrome de hipertensão intracraniana, hiperproteinoraquia sem pleocitose e sinais clínicos ou radiológicos sugestivos de localização na base do crânio a possibilidade de um germinoma quiasmático deve ser seriamente considerada, pois o quadro e muito sugestivo.Three cases of Cerebral Germinomas, one of them situated in the pineal region (topical and two ectopical of the so called suprasellar or chiasmal Germinomas are studied. These last ones may be more aggressive than the congeneral topical ones, since besides it's dissemination throughout the basal cisternas they usually infilstrate into de walls of the III Ventricle, Fornix, Hypothalamus, Chiasma and Optic nervs. A high level of proteins in the spinal fluid without proportional increase of the cells is characteristic. Globulins are the predominant fraction of the increased spinal fluid proteins, as indicated by the highly positive laboratory test. These globulins are possibly produced by the lymphocytes which are part of this neoplasm. The high level of protein in the spinal fluid without proportional increase of the cells, in the presence of intracranial syndrome in a child or adolescent, with anatomical signs of basal localization make the possibility of a Chiasmal Germinona highly probable.

  9. Formation of small sparks

    International Nuclear Information System (INIS)

    Barreto, E.; Jurenka, H.; Reynolds, S.I.

    1977-01-01

    The formation of a small incendiary spark at atmospheric pressure is identified with the transition from a weakly to a strongly ionized plasma. It is shown that initial gaseous ionization produced by avalanches and/or streamers always creates a high-temperature ideal electron gas that can shield the applied voltage difference and reduce ionization in the volume of the gas. The electron gas is collision dominated but able to maintain its high temperature, for times long compared to discharge events, through long-range Coulomb forces. In fact, electrons in the weakly ionized plasma constitute a collisionless independent fluid with a thermodynamic state that can be affected directly by field or density changes. Accordingly, with metal electrodes, cathode spot emission is always associated with the transition to a strongly ionized plasma. Neutral heating can be accomplished in two different ways. Effective dispersal of the electrons from the cathode leads to electron heating dominated by diffusion effects. Conversely, a fast rate of emission or rapid field changes can produce nonlinear wave propagation. It is shown that solitary waves are possible, and it is suggested that some spark transitions are associated with shock waves in the collisionless electron gas. In either the diffuse or nonlinear regime, neutral gas heating is controlled by collisions of ions with isotropic thermal electrons. This interaction is always subsequent to changes in state of the electron gas population. The basic results obtained should apply to all sparks

  10. Large Format Radiographic Imaging

    International Nuclear Information System (INIS)

    Rohrer, J. S.; Stewart, Lacey; Wilke, M. D.; King, N. S.; Baker A, S.; Lewis, Wilfred

    1999-01-01

    Radiographic imaging continues to be a key diagnostic in many areas at Los Alamos National Laboratory (LANL). Radiographic recording systems have taken on many form, from high repetition-rate, gated systems to film recording and storage phosphors. Some systems are designed for synchronization to an accelerator while others may be single shot or may record a frame sequence in a dynamic radiography experiment. While film recording remains a reliable standby in the radiographic community, there is growing interest in investigating electronic recording for many applications. The advantages of real time access to remote data acquisition are highly attractive. Cooled CCD camera systems are capable of providing greater sensitivity with improved signal-to-noise ratio. This paper begins with a review of performance characteristics of the Bechtel Nevada large format imaging system, a gated system capable of viewing scintillators up to 300 mm in diameter. We then examine configuration alternatives in lens coupled and fiber optically coupled electro-optical recording systems. Areas of investigation include tradeoffs between fiber optic and lens coupling, methods of image magnification, and spectral matching from scintillator to CCD camera. Key performance features discussed include field of view, resolution, sensitivity, dynamic range, and system noise characteristics

  11. What Determines Star Formation Rates?

    Science.gov (United States)

    Evans, Neal John

    2017-06-01

    The relations between star formation and gas have received renewed attention. We combine studies on scales ranging from local (within 0.5 kpc) to distant galaxies to assess what factors contribute to star formation. These include studies of star forming regions in the Milky Way, the LMC, nearby galaxies with spatially resolved star formation, and integrated galaxy studies. We test whether total molecular gas or dense gas provides the best predictor of star formation rate. The star formation ``efficiency," defined as star formation rate divided by mass, spreads over a large range when the mass refers to molecular gas; the standard deviation of the log of the efficiency decreases by a factor of three when the mass of relatively dense molecular gas is used rather than the mass of all the molecular gas. We suggest ways to further develop the concept of "dense gas" to incorporate other factors, such as turbulence.

  12. Designing for informed group formation

    DEFF Research Database (Denmark)

    Nicolajsen, Hanne Westh; Juel Jacobsen, Alice; Riis, Marianne

    2012-01-01

    A new design ―project preparation‖ preparing for the group formation in problem based project work is proposed and investigated. The main problem is to overcome group formation based on existing relations. The hypothesis is that theme development and group formation are somewhat counterproductive....... Following research based design methodology an experiment separating the two was initiated.This was to provide for more openness and creativity in contrast to a design in which existing relations seem predominant....

  13. Light meromyosin paracrystal formation.

    Science.gov (United States)

    Chowrashi, P K; Pepe, F A

    1977-07-01

    STUDIES OF PARACRYSTAL FORMATION BY COLUMN PURIFIED LIGHT MEROMYOSIN (LMM) PREPARED IN A VARIETY OF WAYS LED TO THE FOLLOWING CONCLUSIONS: (a) different portions of the myosin rod may be coded for different stagger relationships. This was concluded from observations that paracrystals with different axial repeat periodicities could be obtained either with LMM framents of different lengths prepared with the same enzyme, or with LMM fragments of identical lengths but prepared with different enzymes. (b) Paracrystals with a 14-nm axial repeat periodicity are most likely formed by the aggregation of sheets with a 44-nm axial repeat within the sheets which are staggered by 14 nm. All of the axial repeat patterns expected from one sheet or aggregates of more than one sheet, on this basis, were observed in the same electron micrograph. (c) C-protein binding probably occurs preferentially to LMM molecules related in some specific way. This was concluded from the observation that the same axial repeat pattern was obtained in paracrystals formed from different LMM preparations in the presence of C-protein, regardless of differences in the axial repeat obtained in the absence of C-protein. (d) Nucleic acid is responsible for the 43-nm axial repeat patterns observed in paracrystals formed by the ethanol-resistant fraction of LMM. In the absence of nuclei acid, paracrystals with a 14nm axial repeat are obtained. (e) The 43-nm axial repeat pattern observed with the ethanol-resistant fraction of LMM is different for LMM preparations obtained by trypsin and papain digestions.

  14. Pattern formation during electropolishing

    International Nuclear Information System (INIS)

    Yuzhakov, V.V.; Chang, H.; Miller, A.E.

    1997-01-01

    Using atomic force microscopy, we find that the surface morphology of a dissolving aluminum anode in a commercial electropolishing electrolyte can exhibit both highly regular and randomly packed stripe and hexagonal patterns with amplitudes of about 5 nm and wavelengths of 100 nm. The driving instability of this pattern formation phenomenon is proposed to be the preferential adsorption of polar or polarizable organic molecules on surface ridges where the contorted double layer produces a higher electric potential gradient. The enhanced relative coverage shields the anode and induces a smaller dissolution rate at the ridges. The instability is balanced by surface diffusion of the adsorbate to yield a length scale of 4π(D s /k d ) 1/2 , where D s is the surface diffusivity and k d is the desorption coefficient of the adsorbate, which correlates well with the measured wavelength. A long-wavelength expansion of the double-layer field yields an interface evolution equation that reproduces all of the observed patterns. In particular, bifurcation analysis and numerical simulation yield a single voltage-dependent dimensionless parameter ξ that measures a balance between smoothing of adsorbate concentration by electric-field-dependent surface diffusion and fluctuation due to interfacial curvature and stretching. Randomly oriented stripes are favored at large ξ (low voltage), while random hills dominate at small ξ (high voltage) with perfectly periodic stripes and hexagonal hill patterns within a small window near ξ=1. These predictions are in qualitative and quantitative agreement with our measurements. copyright 1997 The American Physical Society

  15. Formative assessment : Enriching teaching and learning with formative assesment

    NARCIS (Netherlands)

    van Diggelen, M.R.; Morgan, C.M.; Funk, M.; Bruns, M.

    2016-01-01

    Formative assessment is a valuable aspect in teaching and learning, and is proven to be an e ective learning method. There is evidence that adding formative assessment to your teaching increases students’ learning results (Black and William, 1998), but in practice many of the possibilities are left

  16. Formation of interstellar anions

    Science.gov (United States)

    Senent, Maria Luisa

    2012-05-01

    Formation of interstellar anions: M.L. Senent. The recent detection of negative charged species in the ISM1 has instigated enthusiasm for anions in the astrophysical community2. Many of these species are new and entail characterization. How they are formed in astrophysical sources is a question of major relevance. The anion presence in ISM was first predicted theoretically on the basis of electron affinities and on the negative linear chain molecular stabilities. Although very early, they were considered in astrochemical models3-4, their discovery is so recent because their abundances seem to be relatively low. These have to be understood in terms of molecular stabilities, reaction probabilities and radiative and collisional excitations. Then, we present our theoretical work on even carbon chains type Cn and CnH (n=2,4,6) focused to the understanding of anion abundances. We use highly correlated ab initio methods. We performed spectroscopic studies of various isomers that can play important roles as intermediates5-8. In previous papers9-10, we compared C2H and C2H- collisional rates responsible for observed line intensities. Actually, we study hydrogen attachment (Cn +H → CnH and Cn- +H → CnH-) and associative detachment processes (Cn- +H → CnH +e-) for 2, 4 and 6 carbon atom chains11. [1] M.C.McCarthy, C.A.Gottlieb, H.Gupta, P.Thaddeus, Astrophys.J, 652, L141 (2006) [2] V.M.Bierbaum, J.Cernicharo, R.Bachiller, eds., 2011, pp 383-389. [3] A. Dalgarno, R.A. Mc Cray, Astrophys.J,, 181, 95 (1973) [4] E. Herbst E., Nature, 289, 656 (1981); [5] H.Massó, M.L.Senent, P.Rosmus, M.Hochlaf, J.Chem.Phys., 124, 234304 (2006) [6] M.L.Senent, M.Hochlaf, Astrophys. J. , 708, 1452(2010) [7] H.Massó, M.L.Senent, J.Phys.Chem.A, 113, 12404 (2009) [8] D. Hammoutene, M.Hochlaf, M.L.Senent, submitted. [9] A. Spielfiedel, N. Feautrier, F. Najar, D. ben Abdallah, F. Dayou, M.L. Senent, F. Lique, Mon.Not.R.Astron.Soc., 421, 1891 (2012) [10] F.Dumouchel, A, Spielfieldel , M

  17. Satellite formation flying relative dynamics, formation design, fuel optimal maneuvers and formation maintenance

    CERN Document Server

    Wang, Danwei; Poh, Eng Kee

    2017-01-01

    This book systematically describes the concepts and principles for multi-satellite relative motion, passive and near passive formation designs, trajectory planning and control for fuel optimal formation maneuvers, and formation flying maintenance control design. As such, it provides a sound foundation for researchers and engineers in this field to develop further theories and pursue their implementations. Though satellite formation flying is widely considered to be a major advance in space technology, there are few systematic treatments of the topic in the literature. Addressing that gap, the book offers a valuable resource for academics, researchers, postgraduate students and practitioners in the field of satellite science and engineering.

  18. Portable File Format (PFF) specifications

    Energy Technology Data Exchange (ETDEWEB)

    Dolan, Daniel H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-02-01

    Created at Sandia National Laboratories, the Portable File Format (PFF) allows binary data transfer across computer platforms. Although this capability is supported by many other formats, PFF files are still in use at Sandia, particularly in pulsed power research. This report provides detailed PFF specifications for accessing data without relying on legacy code.

  19. Professional Development through Formative Evaluation

    Science.gov (United States)

    Nsibande, Rejoice; Garraway, James

    2011-01-01

    Formative evaluation and its associated methodology of reflection on practice are used extensively in academic staff development. In reflecting on formative evaluation processes in both more traditional and newer programmes conducted at a university of technology, a number of variables reported in the literature were observed to have influenced…

  20. Star formation in the multiverse

    International Nuclear Information System (INIS)

    Bousso, Raphael; Leichenauer, Stefan

    2009-01-01

    We develop a simple semianalytic model of the star formation rate as a function of time. We estimate the star formation rate for a wide range of values of the cosmological constant, spatial curvature, and primordial density contrast. Our model can predict such parameters in the multiverse, if the underlying theory landscape and the cosmological measure are known.

  1. A format for phylogenetic placements.

    Directory of Open Access Journals (Sweden)

    Frederick A Matsen

    Full Text Available We have developed a unified format for phylogenetic placements, that is, mappings of environmental sequence data (e.g., short reads into a phylogenetic tree. We are motivated to do so by the growing number of tools for computing and post-processing phylogenetic placements, and the lack of an established standard for storing them. The format is lightweight, versatile, extensible, and is based on the JSON format, which can be parsed by most modern programming languages. Our format is already implemented in several tools for computing and post-processing parsimony- and likelihood-based phylogenetic placements and has worked well in practice. We believe that establishing a standard format for analyzing read placements at this early stage will lead to a more efficient development of powerful and portable post-analysis tools for the growing applications of phylogenetic placement.

  2. Uranium logging in earth formations

    International Nuclear Information System (INIS)

    Givens, W.W.

    1979-01-01

    A technique is provided for assaying the formations surrounding a borehole for uranium. A borehole logging tool cyclically irradiates the formations with neutrons and responds to neutron fluxes produced during the period of time that prompt neutrons are being produced by the neutron fission of uranium in the formations. A borehole calibration tool employs a steady-state (continuous output) neutron source, firstly, to produce a response to neutron fluxes in models having known concentrations of uranium and, secondly, to to produce a response to neutron fluxes in the formations surrounding the borehole. The neutron flux responses of the borehole calibration tool in both the model and the formations surrounding the borehole are utilized to correct the neutron flux response of the borehole logging tool for the effects of epithermal/thermal neutron moderation, scattering, and absorption within the borehole itself

  3. Geological factors of deposit formation

    International Nuclear Information System (INIS)

    Grushevoj, G.V.

    1980-01-01

    Geologic factors of hydrogenic uranium deposit formation are considered. Structural, formation and lithological-facies factors of deposit formation, connected with zones of stratal oxidation, are characterized. Peculiarities of deposit localization, connected with orogenic structures of Mesozoic and lenozoic age, are described. It is noted that deposits of anagenous group are widely spread in Paleozoic formations, infiltration uranium deposits are localized mainly in Cenozoic sediments, while uranium mineralization both anagenous and infiltration groups are widely developed in Mesozoic sediments. Anagenous deposits were formed in non-oxygen situation, their age varies from 200 to 55 mln years. Infiltration deposit formation is determined by asymmetric oxidation zonation, their age varies from 10 - 40 mln years to dozens of thousand years [ru

  4. Process for fracturing underground formations

    Energy Technology Data Exchange (ETDEWEB)

    Kiel, O M

    1974-01-25

    This invention concerns a process for fracturing underground formations and has as one object the mixing of viscous compositions. Through a borehole, a fluid is injected into the formation. This fluid contains a complex prepared by the reaction of an aliphatic quaternary ammonium compound with a water-soluble compound chosen from monosaccharides, disaccharides, trisaccharides, polysaccharides, and synthetic hydroxylated polymers with long chains. These complexes are formed at temperatures between 20/sup 0/ and 205/sup 0/C. The process also includes production of formation fluid into the borehole.

  5. Free-format RPG IV

    CERN Document Server

    Martin, Jim

    2013-01-01

    This how-to guide offers a concise and thorough introduction to the increased productivity, better readability, and easier program maintenance that comes with the free-format style of programming in RPG IV. Although free-format information is available in IBM manuals, it is not separated from everything else, thereby requiring hours of tedious research to track down the information needed. This book provides everything one needs to know to write RPG IV in the free-format style, and author Jim Martin not only teaches rules and syntax but also explains how this new style of coding has the pot

  6. AGN feedback in galaxy formation

    CERN Document Server

    Antonuccio-Delogu, Vincenzo

    2010-01-01

    During the past decade, convincing evidence has been accumulated concerning the effect of active galactic nuclei (AGN) activity on the internal and external environment of their host galaxies. Featuring contributions from well-respected researchers in the field, and bringing together work by specialists in both galaxy formation and AGN, this volume addresses a number of key questions about AGN feedback in the context of galaxy formation. The topics covered include downsizing and star-formation time scales in massive elliptical galaxies, the connection between the epochs of supermassive black h

  7. DNA methylation and memory formation.

    Science.gov (United States)

    Day, Jeremy J; Sweatt, J David

    2010-11-01

    Memory formation and storage require long-lasting changes in memory-related neuronal circuits. Recent evidence indicates that DNA methylation may serve as a contributing mechanism in memory formation and storage. These emerging findings suggest a role for an epigenetic mechanism in learning and long-term memory maintenance and raise apparent conundrums and questions. For example, it is unclear how DNA methylation might be reversed during the formation of a memory, how changes in DNA methylation alter neuronal function to promote memory formation, and how DNA methylation patterns differ between neuronal structures to enable both consolidation and storage of memories. Here we evaluate the existing evidence supporting a role for DNA methylation in memory, discuss how DNA methylation may affect genetic and neuronal function to contribute to behavior, propose several future directions for the emerging subfield of neuroepigenetics, and begin to address some of the broader implications of this work.

  8. Robust Decentralized Formation Flight Control

    Directory of Open Access Journals (Sweden)

    Zhao Weihua

    2011-01-01

    Full Text Available Motivated by the idea of multiplexed model predictive control (MMPC, this paper introduces a new framework for unmanned aerial vehicles (UAVs formation flight and coordination. Formulated using MMPC approach, the whole centralized formation flight system is considered as a linear periodic system with control inputs of each UAV subsystem as its periodic inputs. Divided into decentralized subsystems, the whole formation flight system is guaranteed stable if proper terminal cost and terminal constraints are added to each decentralized MPC formulation of the UAV subsystem. The decentralized robust MPC formulation for each UAV subsystem with bounded input disturbances and model uncertainties is also presented. Furthermore, an obstacle avoidance control scheme for any shape and size of obstacles, including the nonapriorily known ones, is integrated under the unified MPC framework. The results from simulations demonstrate that the proposed framework can successfully achieve robust collision-free formation flights.

  9. The multifaceted planetesimal formation process

    DEFF Research Database (Denmark)

    Johansen, Anders; Blum, Jürgen; Tanaka, Hidekazu

    2013-01-01

    Accumulation of dust and ice particles into planetesimals is an important step in the planet formation process. Planetesimals are the seeds of both terrestrial planets and the solid cores of gas and ice giants forming by core accretion. Left-over planetesimals in the form of asteroids, trans...... for planetesimal formation where particle growth starts unaided by self-gravity but later proceeds inside gravitationally collapsing pebble clumps to form planetesimals with a wide range of sizes....

  10. Chain formation of metal atoms

    DEFF Research Database (Denmark)

    Bahn, Sune Rastad; Jacobsen, Karsten Wedel

    2001-01-01

    The possibility of formation of single-atomic chains by manipulation of nanocontacts is studied for a selection of metals (Ni, Pd, Pt, Cu, Ag, Au). Molecular dynamics simulations show that the tendency for chain formation is strongest for Au and Pt. Density functional theory calculations indicate...... that the metals which form chains exhibit pronounced many-atom interactions with strong bonding in low coordinated systems....

  11. Cosmic strings and galaxy formation

    Science.gov (United States)

    Bertschinger, Edmund

    1989-01-01

    The cosmogonical model proposed by Zel'dovich and Vilenkin (1981), in which superconducting cosmic strings act as seeds for the origin of structure in the universe, is discussed, summarizing the results of recent theoretical investigations. Consideration is given to the formation of cosmic strings, the microscopic structure of strings, gravitational effects, cosmic string evolution, and the formation of galaxies and large-scale structure. Simulation results are presented in graphs, and several outstanding issues are listed and briefly characterized.

  12. An Adaptable Seismic Data Format

    Science.gov (United States)

    Krischer, Lion; Smith, James; Lei, Wenjie; Lefebvre, Matthieu; Ruan, Youyi; de Andrade, Elliott Sales; Podhorszki, Norbert; Bozdağ, Ebru; Tromp, Jeroen

    2016-11-01

    We present ASDF, the Adaptable Seismic Data Format, a modern and practical data format for all branches of seismology and beyond. The growing volume of freely available data coupled with ever expanding computational power opens avenues to tackle larger and more complex problems. Current bottlenecks include inefficient resource usage and insufficient data organization. Properly scaling a problem requires the resolution of both these challenges, and existing data formats are no longer up to the task. ASDF stores any number of synthetic, processed or unaltered waveforms in a single file. A key improvement compared to existing formats is the inclusion of comprehensive meta information, such as event or station information, in the same file. Additionally, it is also usable for any non-waveform data, for example, cross-correlations, adjoint sources or receiver functions. Last but not least, full provenance information can be stored alongside each item of data, thereby enhancing reproducibility and accountability. Any data set in our proposed format is self-describing and can be readily exchanged with others, facilitating collaboration. The utilization of the HDF5 container format grants efficient and parallel I/O operations, integrated compression algorithms and check sums to guard against data corruption. To not reinvent the wheel and to build upon past developments, we use existing standards like QuakeML, StationXML, W3C PROV and HDF5 wherever feasible. Usability and tool support are crucial for any new format to gain acceptance. We developed mature C/Fortran and Python based APIs coupling ASDF to the widely used SPECFEM3D_GLOBE and ObsPy toolkits.

  13. SUPPLEMENTAL CARDIOPLEGIA IMMEDIATELY BEFORE GRAFT IMPLANTATION MAY IMPROVE EARLY POST-TRANSPLANTATION OUTCOME

    Directory of Open Access Journals (Sweden)

    Hendrik eTevaearai Stahel

    2014-11-01

    Full Text Available Background: Preservation of cardiac grafts for transplantation is not standardized and most centers use a single administration of crystalloid solution at the time of harvesting. We investigated possible benefits of an additional dose of cardioplegia dispensed immediately before implantation.Methods: Consecutive adult cardiac transplantations (2005-2012 were reviewed. Hearts were harvested following a standard protocol (Celsior 2L, 4-8oC. In 2008, 100mL crystalloid cardioplegic solution was added and administered immediately before implantation. Univariate and logistic regression analyses were used to investigate risk factors for post-operative graft failure and mid-term outcome. Results: A total of 81 patients, 44 standard (Cardio - versus 37 with additional cardioplegia (Cardio + were analyzed. Recipients and donors were comparable in both groups. Cardio + patients demonstrated a reduced need for defibrillation (24% vs. 48%, p=0.03, post-operative ratio of CK-MB/CK (10.1±3.9% vs. 13.3±4.2%, p=0.001, intubation time (2.0±1.6 vs. 7.2±11.5 days, p=0.05 and ICU stay (3.9±2.1 vs. 8.5±7.8 days, p=0.001. Actuarial survival was reduced when graft ischemic time was >180 minutes in Cardio – but not in Cardio + patients (p=0.033. Organ ischemic time >180 minutes (OR:5.48, CI:1.08-27.75, donor female gender (OR:5.84, CI:1.13-33.01 and recipient/donor age >60 (OR:6.33, CI:0.86-46.75, but not the additional cardioplegia nor the observation period appeared independent predictors of post-operative acute graft failure.Conclusion: An additional dose of cardioplegia administered immediately before implantation may be a simple way to improve early and late outcome of cardiac transplantation, especially in situations of prolonged graft ischemia. A large, ideally multicentric, randomized study is desirable to verify this preliminary observation.

  14. Posttransplantation primary cutaneous CD30 (Ki-1)-positive large-cell lymphoma.

    Science.gov (United States)

    Seçkin, D; Demirhan, B; Oğuz Güleç, T; Arikan, U; Haberal, M

    2001-12-01

    We describe the case of a 51-year-old female renal transplant recipient with primary cutaneous CD30-positive large-cell lymphoma of T-cell origin. Cutaneous T-cell lymphomas are rarely reported in organ transplant recipients, and we believe they should be considered in the differential diagnosis of cutaneous neoplastic and infectious diseases affecting this patient group.

  15. Angiotensinogen Polymorphisms and Post-Transplantation Diabetes Mellitus in Korean Renal Transplant Subjects

    Directory of Open Access Journals (Sweden)

    Sul ra Lee

    2013-03-01

    Full Text Available Background: Post-transplant diabetes mellitus (PTDM is a common and serious metabolic complication. Genetic polymorphisms of angiotensin-converting enzyme (ACE and angiotensinogen (AGT genes have been reported to be related to diabetes mellitus and insulin sensitivity; however, the role of these genes in the development of PTDM is not known. For this purpose, we investigated the association of ACE and AGT genetic polymorphisms with PTDM. Methods: A total of 302 subjects without previously diagnosed diabetes who had received kidney transplants were included. One ACE single nucleotide polymorphism (SNP (rs4291 and two AGT SNPs (rs 699 and rs 4762 were genotyped from genomic DNA with direct sequencing. Results: PTDM developed in 49 (16.2% of 302 subjects. Subjects in the PTDM were older than those in the non-PTDM. There was a significant difference between the two groups in tacrolimus use (p=0.03. Of the three SNPs, the rs4762 of the AGT gene was significantly associated with the development of PTDM in the dominant models (p = 0.03 after adjusting for age and tacrolimus usage. Conclusions: AGT gene rs4762 polymorphisms may serve as genetic markers for the development of PTDM. The exact molecular mechanisms still need to be clarified.

  16. Pre-liver transplant psychosocial evaluation predicts post-transplantation outcomes.

    Science.gov (United States)

    Benson, Ariel A; Rowe, Mina; Eid, Ahmad; Bluth, Keren; Merhav, Hadar; Khalaileh, Abed; Safadi, Rifaat

    2018-08-01

    Psychosocial factors greatly impact the course of patients throughout the liver transplantation process. A retrospective chart review was performed of patients who underwent liver transplantation at Hadassah-Hebrew University Medical Center between 2002 and 2012. A composite psychosocial score was computed based on the patient's pre-transplant evaluation. Patients were divided into two groups based on compliance, support and insight: Optimal psychosocial score and Non-optimal psychosocial score. Post-liver transplantation survival and complication rates were evaluated. Out of 100 patients who underwent liver transplantation at the Hadassah-Hebrew University Medical Center between 2002 and 2012, 93% had a complete pre-liver transplant psychosocial evaluation in the medical record performed by professional psychologists and social workers. Post-liver transplantation survival was significantly higher in the Optimal group (85%) as compared to the Non-optimal group (56%, p = .002). Post-liver transplantation rate of renal failure was significantly lower in the Optimal group. No significant differences were observed between the groups in other post-transplant complications. A patient's psychosocial status may impact outcomes following transplantation as inferior psychosocial grades were associated with lower overall survival and increased rates of complications. Pre-liver transplant psychosocial evaluations are an important tool to help predict survival following transplantation.

  17. Eculizumab for drug-induced de novo posttransplantation thrombotic microangiopathy: A case report.

    Science.gov (United States)

    Safa, Kassem; Logan, Merranda S; Batal, Ibrahim; Gabardi, Steven; Rennke, Helmut G; Abdi, Reza

    2015-02-01

    De novo thrombotic microangiopathy (TMA) following renal transplantation is a severe complication associated with high rates of allograft failure. Several immunosuppressive agents are associated with TMA. Conventional approaches to managing this entity, such as withdrawal of the offending agent and/or plasmapheresis, often offer limited help, with high rates of treatment failure and graft loss. We herein report a case of drug induced de novo TMA successfully treated using the C5a inhibitor eculizumab in a renal transplant patient. This report highlights a potentially important role for eculizumab in settings where drug-induced de novo TMA is refractory to conventional therapies.

  18. Proceedings from an international consensus meeting on posttransplantation diabetes mellitus : recommendations and future directions

    NARCIS (Netherlands)

    Sharif, A.; Hecking, M.; de Vries, A. P. J.; Porrini, E.; Hornum, M.; Rasoul-Rockenschaub, S.; Berlakovich, G.; Krebs, M.; Kautzky-Willer, A.; Schernthaner, G.; Marchetti, P.; Pacini, G.; Ojo, A.; Takahara, S.; Larsen, J. L.; Budde, K.; Eller, K.; Pascual, J.; Jardine, A.; Bakker, S. J. L.; Valderhaug, T. G.; Jenssen, T. G.; Cohney, S.; Saeemann, M. D.

    A consensus meeting was held in Vienna on September 8-9, 2013, to discuss diagnostic and therapeutic challenges surrounding development of diabetes mellitus after transplantation. The International Expert Panel comprised 24 transplant nephrologists, surgeons, diabetologists and clinical scientists,

  19. Proceedings from an international consensus meeting on posttransplantation diabetes mellitus: recommendations and future directions

    DEFF Research Database (Denmark)

    Sharif, A.; Hecking, M.; de Vries, A.P.

    2014-01-01

    A consensus meeting was held in Vienna on September 8-9, 2013, to discuss diagnostic and therapeutic challenges surrounding development of diabetes mellitus after transplantation. The International Expert Panel comprised 24 transplant nephrologists, surgeons, diabetologists and clinical scientist...

  20. Radioisotope studies in the diagnosis of acute complications in the post-transplantation stage

    International Nuclear Information System (INIS)

    Lopatkin, N.A.; Gleizer, J.J.; Jarmolinskij, J.S.; Darenkov, A.F.

    1980-01-01

    Dynamic scintigraphy with computer renography ( 131 I-hippuran, 125 I-hippuran, sup(99m)Tc-DTPA), indirect angiography (sup(99m)Tc-albumin), static scintigraphy ( 197 Hg-promeran, sup(99m)Tc-citrate, sup(99m)Tc-calcium-gluconate, sup(99m)Tc-sulphuric colloid) and RIA determination of plasma renin activity were carried out in 105 patients with complications after renal transplantation. In the diagnosis of the specific complications the most valuable methods were the following: indirect angiography in the diagnosis of renal arterial thrombosis; dynamic scintigraphy in the case of ureteral occlusion; static scintigraphy ( 197 Hg-promeran) in infarction, carbuncle or abscess of the transplantatum. The methods applied provided ''good'' information in the following cases: indirect angiography in venous thrombosis and acute tubular necrosis; dynamic scintigraphy in venous and arterial thrombosis, ureteral occlusion, and acute renal failure; static scintigraphy with sup(99m)Tc-citrate in infarction and abscessus, with sup(99m)Tc-calcium-gluconate in ureteral occlusion, with sup(99m)Tc-sulphuric colloid in acute tubular necrosis; RIA determination of plasma renin activity in acute tubular necrosis. In the different pathological conditions the examinations not mentioned above gave poor or negative results. (L.E.)

  1. Efficacy and flexibility impact perceived adherence barriers in pediatric kidney post-transplantation.

    Science.gov (United States)

    Guilfoyle, Shanna M; Goebel, Jens W; Pai, Ahna L H

    2011-03-01

    The alarming rates of medication nonadherence and its detrimental effect on long-term graft survival in pediatric kidney transplantation has called attention to identifying modifiable factors that promote better adherence and subsequent transplant outcomes. In a sample of 45 adolescent kidney transplant recipients (14.7 ± 3.3 years, 77.8% Caucasian, 39.5% female) and their primary caregivers, study aims included: 1) identifying sociodemographic and medical correlates of both caregiver- and patient-reported general family functioning (i.e., efficacy, flexibility, and communication) and 2) determining the unique contributions of these family functioning indices to perceived posttransplant adherence barriers. During a routine clinic visit, caregivers completed a sociodemographic form and questionnaire on general family functioning. Both caregivers and the adolescents completed a measure on perceived medication adherence barriers. Data identified household income and family structure as persistent correlates of family functioning. Familial efficacy and flexibility contributed significant variance to perceived adherence barriers. Family-based interventions enhancing modifiable family factors, such as flexibility and efficacy, in overcoming medication adherence barriers would likely promote more optimal health outcomes in the pediatric kidney transplant population. (c) 2011 APA, all rights reserved

  2. Non-HLA antibodies post-transplantation: clinical relevance and treatment in solid organ transplantation.

    Science.gov (United States)

    Dragun, Duska; Hegner, Bjorn

    2009-01-01

    Antibodies and B cells are increasingly recognized as major modulators of allograft function and survival. Improved immunohistochemical and serologic diagnostic procedures have been developed to monitor antibody responses against HLA antigens during the last decade. Acute and chronic allograft rejection can occur in HLA-identical sibling transplants implicating the importance of immune response against non-HLA targets. Non-HLA anti-bodies may occur as alloantiboides, yet they seem to be predominantly autoantibodies. Antigenic targets of non-HLA antibodies described thus far include various minor histocompatibility antigens, vascular receptors, adhesion molecules, and intermediate filaments. Non-HLA antibodies may function as complement- and non-complement-fixing antibodies and they may induce a wide variety of allograft injuries, reflecting the complexity of their acute and chronic actions. Refined approaches considering the subtle mechanistic differences in the individual antibody responses directed against non-HLA antigens may help to define patients at particular risk for irreversible acute or chronic allograft injuries and improve over-all outcomes. We attempted to summarize the current state of research, development in diagnostic and therapeutic strategies, and to address some emerging problems in the area of humoral response against non-HLA antigens beyond ABO blood group and MHC class I chain-related gene A and B (MICA and MICB) antigens in solid organ transplantation. Copyright (c) 2009 S. Karger AG, Basel.

  3. Will Post-Transplantation Cell Therapies for Pediatric Patients Become Standard of Care?

    NARCIS (Netherlands)

    Lankester, Arjan C.; Locatelli, Franco; Bader, Peter; Rettinger, Eva; Egeler, Maarten; Katewa, Satyendra; Pulsipher, Michael A.; Nierkens, Stefan; Schultz, Kirk; Handgretinger, Rupert; Grupp, Stephan A.; Boelens, Jaap Jan; Bollard, Catherine M.

    Although allogeneic hematopoietic stem cell transplantation (HSCT) is a curative approach for many pediatric patients with hematologic malignancies and some nonmalignant disorders, some critical obstacles remain to be overcome, including relapse, engraftment failure, graft-versus-host disease

  4. Review of nutrition labeling formats.

    Science.gov (United States)

    Geiger, C J; Wyse, B W; Parent, C R; Hansen, R G

    1991-07-01

    This article examines nutrition labeling history as well as the findings of nine research studies of nutrition labeling formats. Nutrition labeling regulations were announced in 1973 and have been periodically amended since then. In response to requests from consumers and health care professionals for revision of the labeling system, the Food and Drug Administration initiated a three-phase plan for reform of nutrition labeling in 1990. President Bush signed the Nutrition Labeling and Education Act in November 1990. Literature analysis revealed that only nine studies with an experimental design have focused on nutrition labeling since 1971. Four were conducted before 1975, which was the year that nutrition labeling was officially implemented, two were conducted in 1980, and three were conducted after 1986. Only two of the nine studies supported the traditional label format mandated by the Code of Federal Regulations, and one study partially supported it. Four of the nine studies that evaluated graphic presentations of nutrition information found that consumer comprehension of nutrition information was improved with a graphic format for nutrition labeling: three studies supported the use of bar graphs and one study supported the use of a pie chart. Full disclosure (ie, complete nutrient and ingredient labeling) was preferred by consumers in two of the three studies that examined this variable. The third study supported three types of information disclosure dependent upon socioeconomic class. In those studies that tested graphics, a bar graph format was significantly preferred and showed better consumer comprehension than the traditional format.

  5. Automation of Tabular Application Formation

    Directory of Open Access Journals (Sweden)

    S. V. Zykin

    2013-01-01

    Full Text Available The paper considers automation problems of the interface formation between a table and a relational database. The task description is formalized and the description of the existing approaches to formation of data representations on an example of widely widespread CASE-tools is submitted. The definition of intermediate data representation as a ”join table” is offered, which is used for maintenance of correctness of data representation formation, and also is necessary for direct and inverse data transformations. On the basis of lossless join property and realized dependencies, the concept and a way of context formation of the application and restrictions is introduced. The considered material is further used for constructing an inverse data transformation from tabular presentation into a relational one. On the basis of relationships properties on a database scheme, the partial order on the relations is established, and the restriction of acyclic databases schemes is introduced. The received results are further used at the analysis of principles of formation of inverse data transformation, and the basic details of such a transformation algorithm are considered.

  6. Formative assessment: a student perspective.

    Science.gov (United States)

    Hill, D A; Guinea, A I; McCarthy, W H

    1994-09-01

    An educator's view would be that formative assessment has an important role in the learning process. This study was carried out to obtain a student perspective of the place of formative assessment in the curriculum. Final-year medical students at Royal Prince Alfred Hospital took part in four teaching sessions, each structured to integrate teaching with assessment. Three assessment methods were used; the group objective structured clinical examination (G-OSCE), structured short answer (SSA) questions and a pre/post-test multiple choice questionnaire (MCQ). Teaching sessions were conducted on the subject areas of traumatology, the 'acute abdomen', arterial disorders and cancer. Fifty-five students, representing 83% of those who took part in the programme, responded to a questionnaire where they were asked to rate (on a 5-point Likert scale) their response to general questions about formative assessment and 13 specific questions concerning the comparative value of the three assessment modalities. Eighty-nine per cent of respondents felt that formative assessment should be incorporated into the teaching process. The SSA assessment was regarded as the preferred modality to reinforce previous teaching and test problem-solving skills. The MCQ was the least favoured assessment method. The effect size variable between the total scores for the SSA and MCQ was 0.64. The variable between G-OSCE and SSA/MCQ was 0.26 and 0.33 respectively. Formative assessment is a potentially powerful method to direct learning behaviour. Students should have input into the methods used.

  7. The Physics of Planetesimal Formation

    Science.gov (United States)

    Simon, Jacob; Armitage, Philip; Youdin, Andrew; Li, Rixin

    2015-12-01

    Planetesimals are the precursors to planets, and understanding their formation is an essential step towards developing a complete theory of planet formation. For small solid particles (e.g., dust grains) to coagulate into planetesimals, however, requires that these particles grow beyond centimeter sizes; with traditional coagulation physics, this is very difficult. The streaming instability, which is a clumping process akin to the pile-up of cars in a traffic jam, generates sufficiently high solid densities that the mutual gravity between the clumped particles eventually causes their collapse towards planetesimal mass and size scales. Exploring this transition from dust grains to planetesimals is still in its infancy but is extremely important if we want to understand the basics of planet formation. Here, I present a series of high resolution, first principles numerical simulations of potoplanetary disk gas and dust to study the clumping of particles via the streaming instability and the subsequent collapse towards planetesimals. These simulations have been employed to characterize the planetesimal population as a function of radius in protoplanetary disks. The results of these simulations will be crucial for planet formation models to correctly explain the formation and configuration of solar systems.

  8. Exoplanets Detection, Formation, Properties, Habitability

    CERN Document Server

    Mason, John W

    2008-01-01

    This edited, multi-author volume will be an invaluable introduction and reference to all key aspects in the field of exoplanet research. The reviews cover: Detection methods and properties of known exoplanets, Detection of extrasolar planets by gravitational microlensing. The formation and evolution of terrestrial planets in protoplanetary and debris disks. The brown dwarf-exoplanet connection. Formation, migration mechanisms and properties of hot Jupiters. Dynamics of multiple exoplanet systems. Doppler exoplanet surveys. Searching for exoplanets in the stellar graveyard. Formation and habitability of extra solar planets in multiple star systems. Exoplanet habitats and the possibilities for life. Moons of exoplanets: habitats for life. Contributing authors: •Rory Barnes •David P. Bennett •Jian Ge •Nader Haghighipour •Patrick Irwin •Hugh Jones •Victoria Meadows •Stanimir Metchev •I. Neill Reid •George Rieke •Caleb Scharf •Steinn Sigurdsson

  9. Modularity in New Market Formation

    DEFF Research Database (Denmark)

    Sanchez, Ron; Hang, Chang Chieh

    2017-01-01

    In this paper we appraise the ways in which use of closed-system proprietary product architectures versus open-system modular product architectures is likely to influence the dynamics and trajectory of new product market formation. We compare the evolutions of new markets in China for gas......-powered two-wheeled vehicles (G2WVs) based (initially) on closed-system proprietary architectures and for electric-powered two-wheeled vehicles (E2WVs) based on open-system modular architectures. We draw on this comparison to suggest ways in which the use of the two different kinds of architectures...... as the basis for new kinds of products may result in very different patterns and speeds of new market formation. We then suggest some key implications of the different dynamics of market formation associated with open-system modular architectures for both the competence-based strategic management (CBSM...

  10. Cosmic strings and galaxy formation

    International Nuclear Information System (INIS)

    Bertschinger, E.

    1989-01-01

    Cosmic strings have become increasingly popular candidates as seeds for the formation of structure in the universe. This scenario, remains a serious cosmogonical model despite close scrutiny. In constrast, magnetic monopoles and domain walls - relic topological defects as are cosmic strings - are disastrous for cosmology if they are left over from the early universe. The production of heavy cosmic strings is speculative, as it depends on the details of ultrahigh energy physics. Fortunately, speculation about cosmic strings is not entirely idle because, if they exist and are heavy enough to seed galaxy formation, cosmic strings can be detected astronomically. Failure to detect cosmic strings would impose some constraints on grand unified theories (GUTs); their discovery would have exciting consequences for high energy physics and cosmology. This article reviews the basic physics of nonsuperconducting cosmic strings, highlighting the field theory aspects, and provides a progress report on calculations of structure formation with cosmic strings

  11. 'TV Format Protection through Marketing Strategies?'

    OpenAIRE

    Singh, Sukhpreet

    2008-01-01

    Commercially successful programme ideas are often imitated or adapted. Television formats, in particular, are routinely copied. Starting from radio formats in the 1950s to game shows and reality programme formats of today, producers have accused others of “stealing”. Although formats constitute one of the most important exports for British TV producers, there is still no certainty about the legal protection of TV formats from copycat versions. Since TV formats fail to fall neatly within the d...

  12. Regulation of Reactionary Dentine Formation.

    Science.gov (United States)

    Neves, V C M; Sharpe, P T

    2018-04-01

    During the treatment of dental caries that has not penetrated the tooth pulp, maintenance of as much unaffected dentine as possible is a major goal during the physical removal of decayed mineral. Damage to dentine leads to release of fossilized factors (transforming growth factor-β [TGF-β] and bone morphogenic protein [BMP]) in the dentine that are believed to stimulate odontoblasts to secrete new "tertiary" dentine (reactionary dentine). This is formed on the pulpal surface of existing dentine and rethickens the dentine. We have previously shown that activation of Wnt/β-catenin signaling is pivotal for tooth repair in exposed pulp injury, and the pathway can be activated by small-molecule GSK-3 antagonists, resulting in enhanced reparative dentine formation. Here, we use a nonexposed pulp injury model to investigate the mechanisms of reactionary dentine formation in vivo, using small molecules to modulate the Wnt/β-catenin, TGF-β, and BMP pathways. We found that a local increase of Wnt activation at the injury site enhances reactionary dentine secretion. In addition, inhibition of TGF-β, BMP, or Wnt pathways does not impede reactionary dentine formation, although inhibition of TGF-β and/or BMP signaling does result in more disorganized, nontubular reactionary dentine. This suggests that Wnt/β-catenin signaling plays no major role in the formation of reactionary dentine, but in common with reparative dentine formation, exogenous elevation of Wnt/β-catenin signaling can enhance tertiary dentine formation. Release of latent TGF-β or BMPs from dentine is not required for the deposition of mineral to form reactionary dentine but does play a role in its organization.

  13. Radionuclide migration in geological formations

    International Nuclear Information System (INIS)

    Barbreau, A.; Heremans, R.; Skytte Jensen, B.

    1980-01-01

    Radioactive waste disposal into geological formation is based on the capacity of rocks to confine radioactivity for a long period of time. Radionuclide migration from the repository to the environment depends on different mechanisms and phenomena whose two main ones are groundwater flow and the retention and ion-exchange property of rocks. Many studies are underway presently in EEC countries concerning hydrodynamic characteristics of deep geological formations as well as in radionuclide retention capacity and modelling. Important results have already been achieved which show the complexity of some phenomena and further studies shall principally be developed taking into account real conditions of the repository and its environment

  14. Pattern formations and oscillatory phenomena

    CERN Document Server

    Kinoshita, Shuichi

    2013-01-01

    Patterns and their formations appear throughout nature, and are studied to analyze different problems in science and make predictions across a wide range of disciplines including biology, physics, mathematics, chemistry, material science, and nanoscience. With the emergence of nanoscience and the ability for researchers and scientists to study living systems at the biological level, pattern formation research has become even more essential. This book is an accessible first of its kind guide for scientists, researchers, engineers, and students who require a general introduction to thi

  15. The formation of ice sails

    Science.gov (United States)

    Fowler, A. C.; Mayer, C.

    2017-11-01

    Debris-covered glaciers are prone to the formation of a number of supraglacial geomorphological features, and generally speaking, their upper surfaces are far from level surfaces. Some of these features are due to radiation screening or enhancing properties of the debris cover, but theoretical explanations of the consequent surface forms are in their infancy. In this paper we consider a theoretical model for the formation of "ice sails", which are regularly spaced bare ice features which are found on debris-covered glaciers in the Karakoram.

  16. Market formation and market selection

    NARCIS (Netherlands)

    van Raalte, C.L.J.P.

    1996-01-01

    The organization of markets is an important field of inquiry in modern economic theory. This monograph analyzes models which consider the formation and selection of markets. In these models, markets are organized by middlemen and used by traders. In Part I of the monograph, coalitions of middlemen

  17. A Model of Partnership Formation

    NARCIS (Netherlands)

    Talman, A.J.J.; Yang, Z.F.

    2008-01-01

    This paper presents a model of partnership formation. A set of agents wants to conduct some business or other activities. Agents may act alone or seek a partner for cooperation and need in the latter case to consider with whom to cooperate and how to share the profit in a collaborative and

  18. The Road to Galaxy Formation

    CERN Document Server

    Keel, William C

    2007-01-01

    The formation of galaxies is one of the greatest puzzles in astronomy, the solution is shrouded in the depths of space and time, but has profound implications for the universe we observe today. The book discusses the beginnings of the process from cosmological observations and calculations, considers the broad features of galaxies that we need to explain and what we know of their later history. The author compares the competing theories for galaxy formation and considers the progress expected from new generations of powerful telescopes both on earth and in space. In this second edition the author has retained the observationally-based approach of the first edition, a feature which was particularly well-reviewed: Writing in Nature, Carlton Baugh noted in February 2003 that “It is refreshing, in a market dominated by theorists, to come across a book on galaxy formation written from an observational perspective. The Road to Galaxy Formation should prove to be a handy primer on observations for graduate student...

  19. Analysis of Disulfide Bond Formation

    NARCIS (Netherlands)

    Braakman, Ineke; Lamriben, Lydia; van Zadelhoff, Guus; Hebert, Daniel N.

    2017-01-01

    In this unit, protocols are provided for detection of disulfide bond formation in cultures of intact cells and in an in vitro translation system containing isolated microsomes or semi-permeabilized cells. First, the newly synthesized protein of interest is biosynthetically labeled with radioactive

  20. A model of partnership formation

    NARCIS (Netherlands)

    Talman, A.J.J.; Yang, Z.F.

    2011-01-01

    This paper presents a model of partnership formation. A number of agents want to conduct some business or other activities. Agents may act alone or seek a partner for cooperation and need in the latter case to consider with whom to cooperate and how to share the profit in a collaborative and

  1. Is All Formative Influence Immoral?

    Science.gov (United States)

    Tillson, John

    2018-01-01

    Is it true that all formative influence is unethical, and that we ought to avoid influencing children (and indeed anyone at all)? There are more or less defensible versions of this doctrine, and we shall follow some of the strands of argument that lead to this conclusion. It seems that in maintaining that all influence is immoral, one commits…

  2. Exciton Formation in Disordered Semiconductors

    DEFF Research Database (Denmark)

    Klochikhin, A.; Reznitsky, A.; Permogorov, S.

    1999-01-01

    Stationary luminescence spectra of disordered solid solutions can be accounted by the model of localized excitons. Detailed analysis of the long time decay kinetics of luminescence shows that exciton formation in these systems is in great extent due to the bimolecular reaction of separated carrie...

  3. Auditory and phonetic category formation

    NARCIS (Netherlands)

    Goudbeek, Martijn; Cutler, A.; Smits, R.; Swingley, D.; Cohen, Henri; Lefebvre, Claire

    2017-01-01

    Among infants' first steps in language acquisition is learning the relevant contrasts of the language-specific phonemic repertoire. This learning is viewed as the formation of categories in a multidimensional psychophysical space. Research in the visual modality has shown that for adults, some kinds

  4. Facial Prototype Formation in Children.

    Science.gov (United States)

    Inn, Donald; And Others

    This study examined memory representation as it is exhibited in young children's formation of facial prototypes. In the first part of the study, researchers constructed images of faces using an Identikit that provided the features of hair, eyes, mouth, nose, and chin. Images were varied systematically. A series of these images, called exemplar…

  5. Mantle dynamics following supercontinent formation

    Science.gov (United States)

    Heron, Philip J.

    This thesis presents mantle convection numerical simulations of supercontinent formation. Approximately 300 million years ago, through the large-scale subduction of oceanic sea floor, continental material amalgamated to form the supercontinent Pangea. For 100 million years after its formation, Pangea remained relatively stationary, and subduction of oceanic material featured on its margins. The present-day location of the continents is due to the rifting apart of Pangea, with supercontinent dispersal being characterized by increased volcanic activity linked to the generation of deep mantle plumes. The work presented here investigates the thermal evolution of mantle dynamics (e.g., mantle temperatures and sub-continental plumes) following the formation of a supercontinent. Specifically, continental insulation and continental margin subduction are analyzed. Continental material, as compared to oceanic material, inhibits heat flow from the mantle. Previous numerical simulations have shown that the formation of a stationary supercontinent would elevate sub-continental mantle temperatures due to the effect of continental insulation, leading to the break-up of the continent. By modelling a vigorously convecting mantle that features thermally and mechanically distinct continental and oceanic plates, this study shows the effect of continental insulation on the mantle to be minimal. However, the formation of a supercontinent results in sub-continental plume formation due to the re-positioning of subduction zones to the margins of the continent. Accordingly, it is demonstrated that continental insulation is not a significant factor in producing sub-supercontinent plumes but that subduction patterns control the location and timing of upwelling formation. A theme throughout the thesis is an inquiry into why geodynamic studies would produce different results. Mantle viscosity, Rayleigh number, continental size, continental insulation, and oceanic plate boundary evolution are

  6. Inside-out planet formation

    International Nuclear Information System (INIS)

    Chatterjee, Sourav; Tan, Jonathan C.

    2014-01-01

    The compact multi-transiting planet systems discovered by Kepler challenge planet formation theories. Formation in situ from disks with radial mass surface density, Σ, profiles similar to the minimum mass solar nebula but boosted in normalization by factors ≳ 10 has been suggested. We propose that a more natural way to create these planets in the inner disk is formation sequentially from the inside-out via creation of successive gravitationally unstable rings fed from a continuous stream of small (∼cm-m size) 'pebbles', drifting inward via gas drag. Pebbles collect at the pressure maximum associated with the transition from a magnetorotational instability (MRI)-inactive ('dead zone') region to an inner MRI-active zone. A pebble ring builds up until it either becomes gravitationally unstable to form an ∼1 M ⊕ planet directly or induces gradual planet formation via core accretion. The planet may undergo Type I migration into the active region, allowing a new pebble ring and planet to form behind it. Alternatively, if migration is inefficient, the planet may continue to accrete from the disk until it becomes massive enough to isolate itself from the accretion flow. A variety of densities may result depending on the relative importance of residual gas accretion as the planet approaches its isolation mass. The process can repeat with a new pebble ring gathering at the new pressure maximum associated with the retreating dead-zone boundary. Our simple analytical model for this scenario of inside-out planet formation yields planetary masses, relative mass scalings with orbital radius, and minimum orbital separations consistent with those seen by Kepler. It provides an explanation of how massive planets can form with tightly packed and well-aligned system architectures, starting from typical protoplanetary disk properties.

  7. Stemcell Information: SKIP000385 [SKIP Stemcell Database[Archive

    Lifescience Database Archive (English)

    Full Text Available Teratoma formation ... Yes ... Yes ... National Research Institute for Child Health and Development htt...p://www.ncbi.nlm.nih.gov/geo/ Akihiro Umezawa 梅澤 明弘 Available National Research Institute for Child Health a

  8. Dioxin formation from waste incineration.

    Science.gov (United States)

    Shibamoto, Takayuki; Yasuhara, Akio; Katami, Takeo

    2007-01-01

    There has been great concern about dioxins-polychlorinated dibenzo dioxins (PCDDs), polychlorinated dibenzo furans (PCDFs), and polychlorinated biphenyls (PCBs)-causing contamination in the environment because the adverse effects of these chemicals on human health have been known for many years. Possible dioxin-contamination has received much attention recently not only by environmental scientists but also by the public, because dioxins are known to be formed during the combustion of industrial and domestic wastes and to escape into the environment via exhaust gases from incinerators. Consequently, there is a pressing need to investigate the formation mechanisms or reaction pathways of these chlorinated chemicals to be able to devise ways to reduce their environmental contamination. A well-controlled small-scale incinerator was used for the experiments in the core references of this review. These articles report the investigation of dioxin formation from the combustion of various waste-simulated samples, including different kinds of paper, various kinds of wood, fallen leaves, food samples, polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC), polyvinylidene chloride, polyethylene tetraphthalate (PET), and various kinds of plastic products. These samples were also incinerated with inorganic chlorides (NaCl, KCl, CuCI2, MgCl2, MnCl2, FeCl2, CoCl2, fly ash, and seawater) or organic chlorides (PVC, chlordane, and pentachlorophenol) to investigate the role of chlorine content and/or the presence of different metals in dioxin formation. Some samples, such as newspapers, were burned after they were impregnated with NaCl or PVC, as well as being cocombusted with chlorides. The roles of incineration conditions, including chamber temperatures, O2 concentrations, and CO concentrations, in dioxin formation were also investigated. Dioxins (PCDDs, PCDFs, and coplanar-PCBs) formed in the exhaust gases from a controlled small-scale incinerator, where experimental waste

  9. Consensus formation on coevolving networks: groups' formation and structure

    International Nuclear Information System (INIS)

    Kozma, Balazs; Barrat, Alain

    2008-01-01

    We study the effect of adaptivity on a social model of opinion dynamics and consensus formation. We analyse how the adaptivity of the network of contacts between agents to the underlying social dynamics affects the size and topological properties of groups and the convergence time to the stable final state. We find that, while on static networks these properties are determined by percolation phenomena, on adaptive networks the rewiring process leads to different behaviors: adaptive rewiring fosters group formation by enhancing communication between agents of similar opinion, though it also makes possible the division of clusters. We show how the convergence time is determined by the characteristic time of link rearrangement. We finally investigate how the adaptivity yields nontrivial correlations between the internal topology and the size of the groups of agreeing agents

  10. Stratigraphy and dissolution of the Rustler Formation

    International Nuclear Information System (INIS)

    Bachman, G.O.

    1987-01-01

    This report describes the physical stratigraphy of the Rustler Formation, because the Waste Isolation Pilot Plant will be constructed in salt beds that underlie this formation. Described are subdivisions of the formations, the major karst features, and a proposed method for the formation of Nash Draw. 2 refs., 2 figs

  11. Track formation. Principles and applications

    International Nuclear Information System (INIS)

    Monnin, M.

    1978-01-01

    The principles and technical aspects of track formation in insulating solids are first described. The characteristics of dialectic track detection are discussed from the technical point of view: the nature of the detectors, the chemical treatment, the sensitivity and the environmental conditions of use. The applications are reviewed. The principle of each type of applied research is described and then the applications are listed. When used as a detector, nuclear tracks can provide valuable information in a number of fields: element content determination and wrapping, imaging, radiation dosimetry, environmental studies, technological uses and miscellaneous other applications. The track-formation process can also be used for making well-defined holes; this method allows other applications which are also described. Finally, some possible future applications are mentioned. (author)

  12. Nuclear processing during star formation

    International Nuclear Information System (INIS)

    Newman, M.J.

    1978-01-01

    A preliminary survey was conducted of the thermonuclear energy release expected during star formation. The destruction of primordial deuterium provides substantial amounts of energy at surprisingly low temperatures, and must be considered in any meaningful treatment of star formation carried to stages in which the internal temperature exceeds a few hundred thousand degrees. Significant energy generation from consumption of initial lithium requires higher temperatures, of the order of a few million degrees. Depletion of primordial beryllium and boron may never provide an important energy source. The approach to equilibrium of the carbon--nitrogen cycle is dominant at temperatures approaching those characteristic of the central regions of main sequence stars. The present calculation should serve as a useful guide in choosing those nuclear processes to be included in a more detailed study. 8 figures, 2 tables

  13. Coevolutionary modeling in network formation

    KAUST Repository

    Al-Shyoukh, Ibrahim

    2014-12-03

    Network coevolution, the process of network topology evolution in feedback with dynamical processes over the network nodes, is a common feature of many engineered and natural networks. In such settings, the change in network topology occurs at a comparable time scale to nodal dynamics. Coevolutionary modeling offers the possibility to better understand how and why network structures emerge. For example, social networks can exhibit a variety of structures, ranging from almost uniform to scale-free degree distributions. While current models of network formation can reproduce these structures, coevolutionary modeling can offer a better understanding of the underlying dynamics. This paper presents an overview of recent work on coevolutionary models of network formation, with an emphasis on the following three settings: (i) dynamic flow of benefits and costs, (ii) transient link establishment costs, and (iii) latent preferential attachment.

  14. Star Formation in Dusty Quasars

    Science.gov (United States)

    Lumsden, Stuart; Croom, Scott

    2012-04-01

    Quasar mode feedback is thought to be a crucial ingredient in galaxy formation for luminous merging and star-bursting systems at high redshift. The energy from the active nucleus should cause significant gas outflows, reducing the available free gas reservoir for future star formation. It is currently unknown which observational state best corresponds to the stage at which this "blowout" should occur. We intend to test one possible source population for this transition phase, by studying the molecular gas content in a small, statistically complete sample of 3 K-band selected reddened quasars from the AUS survey. All lie in the redshift range 2

  15. Method for consolidating incompetent formations

    Energy Technology Data Exchange (ETDEWEB)

    Pavlich, J.P.; Calvert, D.G.

    1965-02-23

    An incompetent formation is consolidated and left permeable by first injecting a solidifiable liquid resin, and following this by an organic liquid to set the resin. The liquid resin used may be 3 (glycidyloxy) propyl trimethoxysilane in sufficient concentration to considerably increase the compressive strength of the consolidated zone. The silane may be used in a ratio of between 0.5 and 5% of the total volume of the liquid resin. The liquid resin used may be a phenol-formaldehyde condensation product dispersed in an aliphatic alcohol with from 1 to 4 carbon atoms. The liquid resin used may be an epoxy containing a hardener. The resin may be displaced into the formation by a liquid hydrocarbon. (5 claims)

  16. Othering, identity formation and agency

    Directory of Open Access Journals (Sweden)

    Sune Qvotrup Jensen

    2011-10-01

    Full Text Available The article examines the potentials of the concept of othering to describe identity formation among ethnic minorities. First, it outlines the history of the concept, its contemporary use, as well as some criticisms. Then it is argued that young ethnic minority men in Denmark are subject to intersectional othering, which contains elements of exoticist fascination of the other. On the basis of ethnographic material, it is analysed how young marginalized ethnic minority men react to othering. Two types of reactions are illustrated: 1 capitalization on being positioned as the other, and 2 refusing to occupy the position of the other by disidentification and claims to normality. Finally, it is argued that the concept of othering is well suited for understanding the power structures as well as the historic symbolic meanings conditioning such identity formation, but problematic in terms of agency.

  17. Coevolutionary modeling in network formation

    KAUST Repository

    Al-Shyoukh, Ibrahim; Chasparis, Georgios; Shamma, Jeff S.

    2014-01-01

    Network coevolution, the process of network topology evolution in feedback with dynamical processes over the network nodes, is a common feature of many engineered and natural networks. In such settings, the change in network topology occurs at a comparable time scale to nodal dynamics. Coevolutionary modeling offers the possibility to better understand how and why network structures emerge. For example, social networks can exhibit a variety of structures, ranging from almost uniform to scale-free degree distributions. While current models of network formation can reproduce these structures, coevolutionary modeling can offer a better understanding of the underlying dynamics. This paper presents an overview of recent work on coevolutionary models of network formation, with an emphasis on the following three settings: (i) dynamic flow of benefits and costs, (ii) transient link establishment costs, and (iii) latent preferential attachment.

  18. THE BLACK HOLE FORMATION PROBABILITY

    Energy Technology Data Exchange (ETDEWEB)

    Clausen, Drew; Piro, Anthony L.; Ott, Christian D., E-mail: dclausen@tapir.caltech.edu [TAPIR, Walter Burke Institute for Theoretical Physics, California Institute of Technology, Mailcode 350-17, Pasadena, CA 91125 (United States)

    2015-02-01

    A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P {sub BH}(M {sub ZAMS}). Although we find that it is difficult to derive a unique P {sub BH}(M {sub ZAMS}) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P {sub BH}(M {sub ZAMS}) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P {sub BH}(M {sub ZAMS}) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment.

  19. A study on frost formation

    OpenAIRE

    青木, 和夫

    1986-01-01

    When humid air is exposed to a cold surface whose temperature is below 0 \\C\\, frost deposition occurs and continues to accumulate on the surface. Frost deposition is an important phenomenon in cryogenic industries for use in air conditioners, refrigerators and freeze-out purification, because it causes the drop of thermal efficiency on heat exchangers.This paper presented a review of our previous studies on frost formation with emphasis on the frost growth process, the frost structure, the gr...

  20. Debris Disks: Probing Planet Formation

    OpenAIRE

    Wyatt, Mark C.

    2018-01-01

    Debris disks are the dust disks found around ~20% of nearby main sequence stars in far-IR surveys. They can be considered as descendants of protoplanetary disks or components of planetary systems, providing valuable information on circumstellar disk evolution and the outcome of planet formation. The debris disk population can be explained by the steady collisional erosion of planetesimal belts; population models constrain where (10-100au) and in what quantity (>1Mearth) planetesimals (>10km i...

  1. Kinetically guided colloidal structure formation

    OpenAIRE

    Hecht, Fabian M.; Bausch, Andreas R.

    2016-01-01

    The well-studied self-organization of colloidal particles is predicted to result in a variety of fascinating applications. Yet, whereas self-assembly techniques are extensively explored, designing and producing mesoscale-sized objects remains a major challenge, as equilibration times and thus structure formation timescales become prohibitively long. Asymmetric mesoscopic objects, without prior introduction of asymmetric particles with all its complications, are out of reach––due to the underl...

  2. Formation of a collaborative society

    OpenAIRE

    Buřita, Ladislav; Ondryhal, Vojtěch

    2014-01-01

    The MilUNI knowledge portal, based on the knowledge base developed in ATOM software has been created at the authors' workplace with the aim to form a collaborative society of military universities. The analysis of the collaborative society concept is presented. The description of the MilUNI project is included. Some areas for university cooperation are proposed, as well as the measures facilitating the formation and development of the collaborative society.

  3. THE BLACK HOLE FORMATION PROBABILITY

    International Nuclear Information System (INIS)

    Clausen, Drew; Piro, Anthony L.; Ott, Christian D.

    2015-01-01

    A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P BH (M ZAMS ). Although we find that it is difficult to derive a unique P BH (M ZAMS ) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P BH (M ZAMS ) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P BH (M ZAMS ) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment

  4. The Black Hole Formation Probability

    Science.gov (United States)

    Clausen, Drew; Piro, Anthony L.; Ott, Christian D.

    2015-02-01

    A longstanding question in stellar evolution is which massive stars produce black holes (BHs) rather than neutron stars (NSs) upon death. It has been common practice to assume that a given zero-age main sequence (ZAMS) mass star (and perhaps a given metallicity) simply produces either an NS or a BH, but this fails to account for a myriad of other variables that may effect this outcome, such as spin, binarity, or even stochastic differences in the stellar structure near core collapse. We argue that instead a probabilistic description of NS versus BH formation may be better suited to account for the current uncertainties in understanding how massive stars die. We present an initial exploration of the probability that a star will make a BH as a function of its ZAMS mass, P BH(M ZAMS). Although we find that it is difficult to derive a unique P BH(M ZAMS) using current measurements of both the BH mass distribution and the degree of chemical enrichment by massive stars, we demonstrate how P BH(M ZAMS) changes with these various observational and theoretical uncertainties. We anticipate that future studies of Galactic BHs and theoretical studies of core collapse will refine P BH(M ZAMS) and argue that this framework is an important new step toward better understanding BH formation. A probabilistic description of BH formation will be useful as input for future population synthesis studies that are interested in the formation of X-ray binaries, the nature and event rate of gravitational wave sources, and answering questions about chemical enrichment.

  5. Interactions, Starbursts, and Star Formation

    Directory of Open Access Journals (Sweden)

    Johan H. Knapen

    2015-12-01

    Full Text Available We study how interactions between galaxies affect star formation within them by considering a sample of almost 1500 of the nearest galaxies, all within a distance of ∼45 Mpc. We use the far-IR emission to define the massive star formation rate (SFR, and then normalise the SFR by the stellar mass of the galaxy to obtain the specific star formation rate (SSFR. We explore the distribution of (SSFR with morphological type and with stellar mass. We calculate the relative enhancement of SFR and SSFR for each galaxy by normalising them by the median SFR and SSFR values of individual control samples of similar non-interacting galaxies. We find that both the median SFR and SSFR are enhanced in interacting galaxies, and more so as the degree of interaction is higher. The increase is moderate, reaching a maximum of a factor of 1.9 for the highest degree of interaction (mergers. While the SFR and SSFR are enhanced statistically by interactions, in many individual interacting galaxies they are not enhanced at all. Our study is based on a representative sample of nearby galaxies and should be used to place constraints on studies based on samples of galaxies at larger distances.

  6. Pattern formation in optical resonators

    International Nuclear Information System (INIS)

    Weiss, C O; Larionova, Ye

    2007-01-01

    We review pattern formation in optical resonators. The emphasis is on 'particle-like' structures such as vortices or spatial solitons. On the one hand, similarities impose themselves with other fields of physics (condensed matter, phase transitions, particle physics, fluds/super fluids). On the other hand the feedback is led by the resonator mirrors to bi- and multi-stability of the spatial field structure, which is the basic ingredient for optical information processing. The spatial dimension or the 'parallelism' is the strength of optics compared to electronics (and will have to be employed to fully use the advantages optics offers in information processing). But even in the 'serial' processing tasks of telecoms (e.g. information buffering) spatial resonator solitons can do better than the schemes proposed so far-including 'slow light'. Pattern formation in optical resonators will likely be the key to brain-like information processing like cognition, learning and association; to complement the precise but limited algorithmic capabilities of electronic processing. But even in the short term it will be useful for solving serial optical processing problems. The prospects for technical uses of pattern formation in resonators are one motivation for this research. The fundamental similarities with other fields of physics, on the other hand, inspire transfer of concepts between fields; something that has always proven fruitful for gaining deeper insights or for solving technical problems

  7. Formation mechanisms of metal colloids

    Science.gov (United States)

    Halaciuga, Ionel

    Highly dispersed uniform metallic particles are widely used in various areas of technology and medicine and are likely to be incorporated into many other applications in the future. It is commonly accepted that size, shape and composition of the particles represent critical factors in most applications. Thus, understanding the mechanisms of formation of metal particles and the ways to control the physical (e.g. shape, size) and chemical (e.g. composition) properties is of great importance. In the current research, the formation of uniform silver spheres is investigated experimentally. The parameters that influence the formation of silver particles when concentrated iso-ascorbic acid and silver-polyamine complex solutions are rapidly mixed were studied in the absence of dispersants. We found that by varying the nature of the amine, temperature, concentration of reactants, silver/amine molar ratio, and the nature of the silver salt, the size of the resulting silver particles can be varied in a wide range (0.08--1.5 microm). The silver particles were formed by aggregation of nanosize subunits as substantiated by both electron microscopy and X-ray diffraction techniques and by the vivid rapid color changes during the chemical precipitation process. From the practical standpoint, the goal of this research was to prepare well dispersed spherical silver particles having a relatively smooth surface and a diameter of about 1 microm to satisfy the demands of the current electronic materials market. A two stage particle growth model previously developed to explain the narrow size distribution occurring in synthesis of gold spheres was applied to the present experimental system, and the parameters that control the size distribution characteristics were identified. The kinetic parameter required to match the final particle size was found to be in agreement with the one used previously in modeling formation of gold spheres, suggesting that similar kinetics governs the

  8. Adsorption-induced step formation

    DEFF Research Database (Denmark)

    Thostrup, P.; Christoffersen, Ebbe; Lorensen, Henrik Qvist

    2001-01-01

    Through an interplay between density functional calculations, Monte Carlo simulations and scanning tunneling microscopy experiments, we show that an intermediate coverage of CO on the Pt(110) surface gives rise to a new rough equilibrium structure with more than 50% step atoms. CO is shown to bind...... so strongly to low-coordinated Pt atoms that it can break Pt-Pt bonds and spontaneously form steps on the surface. It is argued that adsorption-induced step formation may be a general effect, in particular at high gas pressures and temperatures....

  9. Formation fracturing by energy waves

    Energy Technology Data Exchange (ETDEWEB)

    Brandon, C W

    1966-11-28

    A method described for recovering oil from an oil strata penetrated by a well bore includes a step of applying fluid pressure to the interior of the well bore across the face of the stratum, and alternately varying the applied fluid pressure, first above and then below the reservoir pressure. This is in order to fracture and break up the face of the strata from internal pressure exerted on the strata. The pressure is affected using liquefied gas at low pressure across the formation.

  10. Formation Flying and Deformable Instruments

    International Nuclear Information System (INIS)

    Rio, Yvon

    2009-01-01

    Astronomers have always attempted to build very stable instruments. They fight all that can cause mechanical deformation or image motion. This has led to well established technologies (autoguide, active optics, thermal control, tip/tilt correction), as well as observing methods based on the use of controlled motion (scanning, micro scanning, shift and add, chopping and nodding). Formation flying disturbs this practice. It is neither possible to reduce the relative motion to very small amplitudes, nor to control it at will. Some impacts on Simbol-X instrument design, and operation are presented.

  11. Formation Flying and Deformable Instruments

    Science.gov (United States)

    Rio, Yvon

    2009-05-01

    Astronomers have always attempted to build very stable instruments. They fight all that can cause mechanical deformation or image motion. This has led to well established technologies (autoguide, active optics, thermal control, tip/tilt correction), as well as observing methods based on the use of controlled motion (scanning, micro scanning, shift and add, chopping and nodding). Formation flying disturbs this practice. It is neither possible to reduce the relative motion to very small amplitudes, nor to control it at will. Some impacts on Simbol-X instrument design, and operation are presented.

  12. Formative flow in bedrock canyons

    Science.gov (United States)

    Venditti, J. G.; Kwoll, E.; Rennie, C. D.; Church, M. A.

    2017-12-01

    In alluvial channels, it is widely accepted that river channel configuration is set by a formative flow that represents a balance between the magnitude and frequency of flood flows. The formative flow is often considered to be one that is just capable of filling a river channel to the top of its banks. Flows much above this formative flow are thought to cause substantial sediment transport and rearrange the channel morphology to accommodate the larger flow. This idea has recently been extended to semi-alluvial channels where it has been shown that even with bedrock exposed, the flows rarely exceed that required to entrain the local sediment cover. What constitutes a formative flow in a bedrock canyon is not clear. By definition, canyons have rock walls and are typically incised vertically, removing the possibility of the walls being overtopped, as can occur in an alluvial channel at high flows. Canyons are laterally constrained, have deep scour pools and often have width to maximum depth ratios approaching 1, an order of magnitude lower than alluvial channels. In many canyons, there are a sequence of irregularly spaced scour pools. The bed may have intermittent or seasonal sediment cover, but during flood flows the sediment bed is entrained leaving a bare bedrock channel. It has been suggested that canyons cut into weak, well-jointed rock may adjust their morphology to the threshold for block plucking because the rock bed is labile during exceptionally large magnitude flows. However, this hypothesis does not apply to canyons cut into massive crystalline rock where abrasion is the dominant erosion process. Here, we argue that bedrock canyon morphology is adjusted to a characteristic flow structure developed in bedrock canyons. We show that the deeply scoured canyon floor is adjusted to a velocity inversion that is present at low flows, but gets stronger at high flows. The effect is to increase boundary shear stresses along the scour pool that forms in constricted

  13. Transient formation of forbidden lines

    International Nuclear Information System (INIS)

    Rosmej, F.B.; Rosmej, O.N.

    1996-01-01

    An explanation of anomalously long time scales in the transient formation of forbidden lines is proposed. The concept is based on a collisionally induced density dependence of the relaxation times of metastable level populations in transient plasma. Generalization leads to an incorporation of diffusion phenomena. We demonstrate this new concept for the simplest atomic system: the He-like isoelectronic sequence. A new interpretation of the observed long duration and anomalously high intensity of spin-forbidden emission in hot plasmas is given. (author)

  14. Salt formations offer disposal alternative

    International Nuclear Information System (INIS)

    Funderburk, R.

    1990-01-01

    This paper discusses how three U.S. firms are spending millions to permit and build underground disposal sites in salt formations. These companies claim salt is the ideal geological medium for holding hazardous wastes. Two Texas locations and one in Michigan have been targeted as future sites for hazardous waste disposal. The Michigan site, outside Detroit, is a former salt mine 2,000 feet beneath the Ford Motor Co. (Detroit) assembly works in Dearborn. Both Texas sites are atop salt domes---one east and one west of Houston

  15. Transient formation of forbidden lines

    Energy Technology Data Exchange (ETDEWEB)

    Rosmej, F.B. [Bochum Univ., Ruhr (Germany). Inst. fuer Experimentalphysik V; Rosmej, O.N. [VNIIFTRI, Moscow Region (Russian Federation). MISDC

    1996-05-14

    An explanation of anomalously long time scales in the transient formation of forbidden lines is proposed. The concept is based on a collisionally induced density dependence of the relaxation times of metastable level populations in transient plasma. Generalization leads to an incorporation of diffusion phenomena. We demonstrate this new concept for the simplest atomic system: the He-like isoelectronic sequence. A new interpretation of the observed long duration and anomalously high intensity of spin-forbidden emission in hot plasmas is given. (author).

  16. Tube Formation in Nanoscale Materials

    Directory of Open Access Journals (Sweden)

    Yan Chenglin

    2008-01-01

    Full Text Available Abstract The formation of tubular nanostructures normally requires layered, anisotropic, or pseudo-layered crystal structures, while inorganic compounds typically do not possess such structures, inorganic nanotubes thus have been a hot topic in the past decade. In this article, we review recent research activities on nanotubes fabrication and focus on three novel synthetic strategies for generating nanotubes from inorganic materials that do not have a layered structure. Specifically, thermal oxidation method based on gas–solid reaction to porous CuO nanotubes has been successfully established, semiconductor ZnS and Nb2O5nanotubes have been prepared by employing sacrificial template strategy based on liquid–solid reaction, and an in situ template method has been developed for the preparation of ZnO taper tubes through a chemical etching reaction. We have described the nanotube formation processes and illustrated the detailed key factors during their growth. The proposed mechanisms are presented for nanotube fabrication and the important pioneering studies are discussed on the rational design and fabrication of functional materials with tubular structures. It is the intention of this contribution to provide a brief account of these research activities.

  17. Supercoil Formation During DNA Melting

    Science.gov (United States)

    Sayar, Mehmet; Avsaroglu, Baris; Kabakcioglu, Alkan

    2009-03-01

    Supercoil formation plays a key role in determining the structure-function relationship in DNA. Biological and technological processes, such as protein synthesis, polymerase chain reaction, and microarrays relys on separation of the two strands in DNA, which is coupled to the unwinding of the supercoiled structure. This problem has been studied theoretically via Peyrard-Bishop and Poland-Scheraga type models, which include a simple representation of the DNA structural properties. In recent years, computational models, which provide a more realtistic representaion of DNA molecule, have been used to study the melting behavior of short DNA chains. Here, we will present a new coarse-grained model of DNA which is capable of simulating sufficiently long DNA chains for studying the supercoil formation during melting, without sacrificing the local structural properties. Our coarse-grained model successfully reproduces the local geometry of the DNA molecule, such as the 3'-5' directionality, major-minor groove structure, and the helical pitch. We will present our initial results on the dynamics of supercoiling during DNA melting.

  18. Vascular pattern formation in plants.

    Science.gov (United States)

    Scarpella, Enrico; Helariutta, Ykä

    2010-01-01

    Reticulate tissue systems exist in most multicellular organisms, and the principles underlying the formation of cellular networks have fascinated philosophers, mathematicians, and biologists for centuries. In particular, the beautiful and varied arrangements of vascular tissues in plants have intrigued mankind since antiquity, yet the organizing signals have remained elusive. Plant vascular tissues form systems of interconnected cell files throughout the plant body. Vascular cells are aligned with one another along continuous lines, and vascular tissues differentiate at reproducible positions within organ environments. However, neither the precise path of vascular differentiation nor the exact geometry of vascular networks is fixed or immutable. Several recent advances converge to reconcile the seemingly conflicting predictability and plasticity of vascular tissue patterns. A control mechanism in which an apical-basal flow of signal establishes a basic coordinate system for body axis formation and vascular strand differentiation, and in which a superimposed level of radial organizing cues elaborates cell patterns, would generate a reproducible tissue configuration in the context of an underlying robust, self-organizing structure, and account for the simultaneous regularity and flexibility of vascular tissue patterns. Copyright 2010 Elsevier Inc. All rights reserved.

  19. Beaver assisted river valley formation

    Science.gov (United States)

    Westbrook, Cherie J.; Cooper, D.J.; Baker, B.W.

    2011-01-01

    We examined how beaver dams affect key ecosystem processes, including pattern and process of sediment deposition, the composition and spatial pattern of vegetation, and nutrient loading and processing. We provide new evidence for the formation of heterogeneous beaver meadows on riverine system floodplains and terraces where dynamic flows are capable of breaching in-channel beaver dams. Our data show a 1.7-m high beaver dam triggered overbank flooding that drowned vegetation in areas deeply flooded, deposited nutrient-rich sediment in a spatially heterogeneous pattern on the floodplain and terrace, and scoured soils in other areas. The site quickly de-watered following the dam breach by high stream flows, protecting the deposited sediment from future re-mobilization by overbank floods. Bare sediment either exposed by scouring or deposited by the beaver flood was quickly colonized by a spatially heterogeneous plant community, forming a beaver meadow. Many willow and some aspen seedlings established in the more heavily disturbed areas, suggesting the site may succeed to a willow carr plant community suitable for future beaver re-occupation. We expand existing theory beyond the beaver pond to include terraces within valleys. This more fully explains how beavers can help drive the formation of alluvial valleys and their complex vegetation patterns as was first postulated by Ruedemann and Schoonmaker in 1938. ?? 2010 John Wiley & Sons, Ltd.

  20. Enthalpy of formation of zircon

    International Nuclear Information System (INIS)

    Ellison, A.J.G.; Navrotsky, A.

    1992-01-01

    Using high-temperature solution calorimetry in molt 2PbO · B 2 O 3 , the enthalpy of reaction of the formation of zircon, ZrSiO 4 , from its constituent oxides has been determined: Δ 4 H 977 (ZrSiO 4 ) = -27.9 (±1.9) kJ/mol. With previously reported data for the heat contents of ZrO 2 SiO 2 and ZrSiO 4 and standard-state enthalpies of formation of ZrO 2 and SiO 2 , we obtain Δ f H 298 degrees. (ZrSiO 4 ) = -2034.2 (±3.1) kJ/mol and Δ t G 298 degrees (ZrSiO 4 ) = -1919.8 kJ/mol. The free energy value is in excellent agreement with a range previously estimated from solid-state reaction equilibria. At higher temperature also the data are in close agreement with existing data, though the data sets diverge somewhat with increasing T. In this paper the limitations of the data for predicting the breakdown temperature of zircon into its constituent oxides are discussed

  1. Spiral branches and star formation

    International Nuclear Information System (INIS)

    Zasov, A.V.

    1974-01-01

    Origin of spiral branches of galaxies and formation of stars in them are considered from the point of view of the theory of the gravitational gas condensation, one of comparatively young theories. Arguments are presented in favour of the stellar condensation theory. The concept of the star formation of gas is no longer a speculative hypothesis. This is a theory which assumes quantitative verification and explains qualitatively many facts observed. And still our knowledge on the nature of spiral branches is very poor. It still remains vague what processes give origin to spiral branches, why some galaxies have spirals and others have none. And shapes of spiral branches are diverse. Some cases are known when spiral branches spread outside boundaries of galaxies themselves. Such spirals arise exclusively in the region where there are two or some interacting galaxies. Only first steps have been made in the explanation of the galaxy spiral branches, and it is necessary to carry out new observations and new theoretical calculations

  2. The Formation Mechanism of Hydrogels.

    Science.gov (United States)

    Lu, Liyan; Yuan, Shiliang; Wang, Jing; Shen, Yun; Deng, Shuwen; Xie, Luyang; Yang, Qixiang

    2017-06-12

    Hydrogels are degradable polymeric networks, in which cross-links play a vital role in structure formation and degradation. Cross-linking is a stabilization process in polymer chemistry that leads to the multi-dimensional extension of polymeric chains, resulting in network structures. By cross-linking, hydrogels are formed into stable structures that differ from their raw materials. Generally, hydrogels can be prepared from either synthetic or natural polymers. Based on the types of cross-link junctions, hydrogels can be categorized into two groups: the chemically cross-linked and the physically cross-linked. Chemically cross-linked gels have permanent junctions, in which covalent bonds are present between different polymer chains, thus leading to excellent mechanical strength. Although chemical cross-linking is a highly resourceful method for the formation of hydrogels, the cross-linkers used in hydrogel preparation should be extracted from the hydrogels before use, due to their reported toxicity, while, in physically cross-linked gels, dissolution is prevented by physical interactions, such as ionic interactions, hydrogen bonds or hydrophobic interactions. Physically cross-linked methods for the preparation of hydrogels are the alternate solution for cross-linker toxicity. Both methods will be discussed in this essay. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  3. Dark matter and galaxy formation

    International Nuclear Information System (INIS)

    Umemura, Masayuki

    1987-01-01

    We propose a hybrid model of universe for galaxy formation, that is, an Einstein- de Sitter universe dominated by two-component dark matter: massive neutrinos and cold dark matter. In this hybrid model, the first luminous objects are dwarf galaxies. The neutrino density fluctuations produce large-scale high density and low density regions, which consequently evolve to superclusters of galaxies and voids, respectively. Dwarf galaxies are formed preferentially in supercluster regions. In voids, the formation of dwarf galaxies is fairly suppressed by diffuse UV flux from QSOs, and instead a number of expanding clouds are born, which produce Lyα forest as seen in QSO spectra. Ordinary galaxies are expected to form as aggregations of dwarf galaxies. In this model, some galaxies are born also in voids, and they tend to evolve to spiral galaxies. Additionally, if the same number of globular clusters are formed in a dwarf, the specific globular cluster frequencies are expected to be much larger in ellipticals than in spirals. (author)

  4. Enamel formation and amelogenesis imperfecta.

    Science.gov (United States)

    Hu, Jan C-C; Chun, Yong-Hee P; Al Hazzazzi, Turki; Simmer, James P

    2007-01-01

    Dental enamel is the epithelial-derived hard tissue covering the crowns of teeth. It is the most highly mineralized and hardest tissue in the body. Dental enamel is acellular and has no physiological means of repair outside of the protective and remineralization potential provided by saliva. Enamel is comprised of highly organized hydroxyapatite crystals that form in a defined extracellular space, the contents of which are supplied and regulated by ameloblasts. The entire process is under genetic instruction. The genetic control of amelogenesis is poorly understood, but requires the activities of multiple components that are uniquely important for dental enamel formation. Amelogenesis imperfecta (AI) is a collective designation for the variety of inherited conditions displaying isolated enamel malformations, but the designation is also used to indicate the presence of an enamel phenotype in syndromes. Recently, genetic studies have demonstrated the importance of genes encoding enamel matrix proteins in the etiology of isolated AI. Here we review the essential elements of dental enamel formation and the results of genetic analyses that have identified disease-causing mutations in genes encoding enamel matrix proteins. In addition, we provide a fresh perspective on the roles matrix proteins play in catalyzing the biomineralization of dental enamel. Copyright 2007 S. Karger AG, Basel.

  5. Package Formats for Preserved Digital Material

    DEFF Research Database (Denmark)

    Zierau, Eld

    2012-01-01

    This paper presents an investigation of the best suitable package formats for long term digital preservation. The choice of a package format for preservation is crucial for future access, thus a thorough analysis of choice is important. The investigation presented here covers setting up requireme......This paper presents an investigation of the best suitable package formats for long term digital preservation. The choice of a package format for preservation is crucial for future access, thus a thorough analysis of choice is important. The investigation presented here covers setting up...... requirements for package formats used for long term preserved digital material, and using these requirements as the basis for analysing a range of package formats. The result of the concrete investigation is that the WARC format is the package format best suited for the listed requirements. Fulfilling...

  6. Negative ion formation processes: A general review

    International Nuclear Information System (INIS)

    Alton, G.D.

    1990-01-01

    The principal negative ion formation processes will be briefly reviewed. Primary emphasis will be placed on the more efficient and universal processes of charge transfer and secondary ion formation through non-thermodynamic surface ionization. 86 refs., 20 figs

  7. FORMATE-BASED FLUIDS: FORMULATION AND APPLICATION

    Directory of Open Access Journals (Sweden)

    Nediljka Gaurina-Međimurec

    2008-12-01

    Full Text Available Formate-based fluids has been successfully used in over hunders HPHT well operations since they introduced in field practice. They have many advantages when compared with conventional HPHT drilling and completion fluids such as: minimal formation damage, maintenance of additve properties at high temperatures, reduced hydraulic flow resistance, low potential for differential sticking, naturally lubricating, very low corrosion rates, biodegradable and pose little risk to the environment etc. Formate-based fluids can be applied during deep slim hole drilling, shale drilling, reservoir drilling, salt and gas hydrate formations drilling. The laboratory research was carried out to evaluate the rheological behavior of formate-based fluids as a function of temperature. Formate-based fluids were formulated using potassium formate brine, xanthan polymer, PAC, starch and calcium carbonate. Experimental results show that potassium formate improves the thermal stability of polymers.

  8. Satellite Formation Control Using Atmospheric Drag

    National Research Council Canada - National Science Library

    Hajovsky, Blake B

    2007-01-01

    This study investigates the use of a linear quadratic terminal controller to reconfigure satellite formations using atmospheric drag actuated control while minimizing the loss of energy of the formation...

  9. Formation of tax culture in Russia

    Directory of Open Access Journals (Sweden)

    Halikova Je.A.

    2014-11-01

    Full Text Available This article deals with the mechanism of the formation of tax culture in Russia, moral and ethical principles, on which based the work of the tax authorities, given the author's idea of the formation of tax culture. We consider the institution of tax advice, its interaction with the tax authorities and its impact on the formation of tax culture.

  10. Formative Constructs Implemented via Common Factors

    Science.gov (United States)

    Treiblmaier, Horst; Bentler, Peter M.; Mair, Patrick

    2011-01-01

    Recently there has been a renewed interest in formative measurement and its role in properly specified models. Formative measurement models are difficult to identify, and hence to estimate and test. Existing solutions to the identification problem are shown to not adequately represent the formative constructs of interest. We propose a new two-step…

  11. ENDF/B-5 formats manual 1984

    Energy Technology Data Exchange (ETDEWEB)

    Kinsey, R; Magurno, B A

    1986-09-01

    The ENDF-5 Format, originally the format of the US Evaluated Nuclear Data File ENDF/B-5, was internationally recommended for the computer storage, processing and exchange of evaluated neutron nuclear data. The present document contains the original Formats Manual of 1979, updated with revisions of Nov. 1983. (author) Figs, tabs

  12. String Formatting Considered Harmful for Novice Programmers

    Science.gov (United States)

    Hughes, Michael C.; Jadud, Matthew C.; Rodrigo, Ma. Mercedes T.

    2010-01-01

    In Java, "System.out.printf" and "String.format" consume a specialised kind of string commonly known as a format string. In our study of first-year students at the Ateneo de Manila University, we discovered that format strings present a substantial challenge for novice programmers. Focusing on their first laboratory we found…

  13. The forensics of fulgurite formation

    Science.gov (United States)

    Pasek, Matthew A.; Pasek, Virginia D.

    2018-04-01

    Natural disasters such as forest fires can result in extensive and costly property damage. These events may be the result of a human error or system failure triggered by electrical discharge, and in such circumstances may form a fulgurite. Understanding fulgurites and their formation may be critical in determining the cause of the fire or other, shock-related event. Here we identify several distinguishing features of fulgurites formed in association with downed power lines, including the presence of melted conductors, transformation of quartz to cristobalite, and morphological differences including increased glass percentage and smaller internal voids. These features are consequences of how heat is transferred to and through a target rock material as it melts and forms a fulgurite, and are predicted from both first principles of diffusive heat transfer, and empirically-derived reaction kinetics for mineral transformations.

  14. The dynamics of fragment formation

    International Nuclear Information System (INIS)

    Keane, D.

    1994-09-01

    We demonstrate that in the Quantum Molecular Dynamics model, dynamical correlations can result in the production rate for final state nucleon clusters (and hence composite fragments) being higher than would be expected if statistics and the available phase space were dominant in determining composite formation. An intranuclear cascade or a Boltzmann-Uehling-Uhlenbeck model, combined with a statistical approach in the late stage of the collision to determine composites, provides an equivalent description only under limited conditions of centrality and beam energy. We use data on participant fragment production in Au + Au collisions in the Bevalac's BOS time projection chamber to map out the parameter space where statistical clustering provides a good description. In particular, we investigate momentum-space densities of fragments up to 4 He as a function of fragment transverse momentum, azimuth relative to the reaction plane, rapidity, multiplicity and beam energy

  15. Field experiments in salt formations

    International Nuclear Information System (INIS)

    Kuehn, K.

    1986-01-01

    Field experiments in salt formations started as early as 1965 with Project Salt Vault in the Lyons Mine, Kansas, U.S.A., and with the purchase of the Asse salt mine by the German Federal Government. Underground tests concentrated on the heat dissipation around buried high-level radioactive wastes and the geomechanical consequences of their disposal. Near-field investigations cover the properties of water and gas release, radiolysis and corrosion. Further objectives of field experiments are the development and underground testing of a handling system for high-level wastes. The performance of an underground test disposal for such wastes is not only considered to be necessary for technical and scientific reasons but also for improving public acceptance of the concept of radioactive waste disposal. (author)

  16. Complexity of formation in holography

    International Nuclear Information System (INIS)

    Chapman, Shira; Marrochio, Hugo; Myers, Robert C.

    2017-01-01

    It was recently conjectured that the quantum complexity of a holographic boundary state can be computed by evaluating the gravitational action on a bulk region known as the Wheeler-DeWitt patch. We apply this complexity=action duality to evaluate the ‘complexity of formation’ (DOI: 10.1103/PhysRevLett.116.191301; 10.1103/PhysRevD.93.086006), i.e. the additional complexity arising in preparing the entangled thermofield double state with two copies of the boundary CFT compared to preparing the individual vacuum states of the two copies. We find that for boundary dimensions d>2, the difference in the complexities grows linearly with the thermal entropy at high temperatures. For the special case d=2, the complexity of formation is a fixed constant, independent of the temperature. We compare these results to those found using the complexity=volume duality.

  17. Infrared Astronomy and Star Formation

    International Nuclear Information System (INIS)

    Evans, N.J.

    1985-01-01

    Infrared astronomy is a natural tool to use in studying star formation because infrared light penetrates the surrounding dust and because protostars are expected to emit infrared light. Infrared mapping and photometry have revealed many compact sources, often embedded in more extensive warm dust associated with a molecular cloud core. More detailed study of these objects is now beginning, and traditional interpretations are being questioned. Some compact sources are now thought to be density enhancements which are not self-luminous. Infrared excesses around young stars may not always be caused by circumstellar dust; speckle measurements have shown that at least some of the excess toward T Tauri is caused by an infrared companion. Spectroscopic studies of the dense, star-forming cores and of the compact objects themselves have uncovered a wealth of new phenomena, including the widespread occurence of energetic outflows. New discoveries with IRAS and with other planned infrared telescopes will continue to advance this field. (author)

  18. Strategy Formation in Eastern Jutland

    DEFF Research Database (Denmark)

    Olesen, Kristian

    2008-01-01

      In Eastern Jutland a strategy formation process has been initiated with the aim of developing a strategic spatial plan for the city region.  An organisation has been set up to deal with the first phase of the process, which is to carry out three functional analyses and prepare a common vision...... in the area.   The municipalities acknowledge the articulation of the city region and the initiated planning process.  However, the municipalities might see the arena as means to lobby for infrastructure investments in Eastern Jutland, as it is doubtful whether the municipalities will feel encouraged to enter...... a process, which is aiming at increasing the national regulation within their territory.    The result might very well be that the discussion about future infrastructure investments is not linked to discussions about future urban development in Eastern Jutland.  These aspects raises serious questions about...

  19. Formation and support of prominence

    International Nuclear Information System (INIS)

    Forbes, T.G.

    1986-01-01

    A short introduction is given to the concepts discussed by the group on the formation and support of prominences. Only quiescent and long-lived active region prominences were considered, since transient prominence phenomena, such as sprays, surges, H alpha flare-loops, and coronal rain, are dynamically distinct from long-lived, prominences. Stable prominences (which are often referred to as filaments when seen against the disk) can be subdivided into three categories, namely active region prominences, quiescent prominences and polar crown prominences. The third category is closely related to the second since a quiescent prominence will eventually evolve into a polar crown prominence if it lasts long enough. The distinction between the first and second categories is not sharp either since intermediates exist here as well (Martin, 1973)

  20. New Office Software course format

    CERN Multimedia

    HR Department

    2010-01-01

    Always interested to anticipate your training needs, the Technical Training service is pleased to propose two new Office Software course formats : “Focus on... ” : On a monthly basis we will propose a theme such as “Sharepoint Collaboration Workspace” or “Word 2007” or “charts” etc. You will have to send us in advance your questions regarding the proposed topic and register for the course through our Training Catalogue. During the session, our trainer will answer all the questions received and participants will increase their knowledge thanks to the solutions discussed for everyone. The course will last two hours, from 09h00 to 11h00 - with open questions on the proposed topic at the end. “Office software Individual coaching”: If one or several particular topics cause you sleepless nights, you can get the help of our trainer who will come to your workplace for a multiple of 1-hour slots . All fields ...

  1. Accretion Processes in Star Formation

    DEFF Research Database (Denmark)

    Küffmeier, Michael

    for short-lived radionuclides that enrich the cloud as a result of supernova explosions of the massive stars allows us to analyze the distribution of the short-lived radionuclides around young forming stars. In contradiction to results from highly-idealized models, we find that the discrepancy in 26 Al...... that the accretion process of stars is heterogeneous in space, time and among different protostars. In some cases, disks form a few thousand years after stellar birth, whereas in other cases disk formation is suppressed due to efficient removal of angular momentum. Angular momentum is mainly transported outward...... with potentially observable fluctuations in the luminosity profile that are induced by variations in the accretion rate. Considering that gas inside protoplanetary disks is not fully ionized, I implemented a solver that accounts for nonideal MHD effects into a newly developed code framework called dispatch...

  2. String Formation Beyond Leading Colour

    CERN Document Server

    Christiansen, Jesper R.

    2015-08-03

    We present a new model for the hadronisation of multi-parton systems, in which colour correlations beyond leading $N_C$ are allowed to influence the formation of confining potentials (strings). The multiplet structure of $SU(3)$ is combined with a minimisation of the string potential energy, to decide between which partons strings should form, allowing also for "baryonic" configurations (e.g., two colours can combine coherently to form an anticolour). In $e^+e^-$collisions, modifications to the leading-colour picture are small, suppressed by both colour and kinematics factors. But in $pp$ collisions, multi-parton interactions increase the number of possible subleading connections, counteracting their naive $1/N_C^2$ suppression. Moreover, those that reduce the overall string lengths are kinematically favoured. The model, which we have implemented in the PYTHIA 8 generator, is capable of reaching agreement not only with the important $\\left(n_\\mathrm{charged})$ distribution but also with measured rates (and ra...

  3. Restucturing the Project Work Format

    DEFF Research Database (Denmark)

    Dupont, Søren

    2015-01-01

    The chapter is based on an evaluation of a pedagogical experiment at Roskilde University, the Antology Experiment. The objective of the experiment was to develop and expand the framework for project work through the production of anthologies compiled collectively by a number of project groups....... The novel aspects of the Anthology Experiment were most notably its magnitude and complexity. In this experiment the groups were totalling some 50 students who were working together. The experiment used a well-known publishing format from research, namely the anthology form, which usually focuses...... on a specific research topic and includes contributions from various researchers. In the Anthology Experiment, the project groups could be viewed as ‘research units’ that produce the contributions to the anthology. The complexity of the experiment offered challenges, both for students and supervisors...

  4. Price formation and market mechanisms

    International Nuclear Information System (INIS)

    Neff, T.L.

    1991-01-01

    World markets for nuclear fuel have changed greatly since the 1970s. In earlier days, firms specializing in mining, conversion, enrichment and fabrication negotiated directly with end users, primarily under long term contracts at specified prices. This old model is gone. Market structure has been transformed: traditional suppliers now compete with traders, some of whom can offer a much larger menu of products and terms than primary suppliers. Utilities act as traders, converters as brokers, brokers as traders, producers as buyers, and so on. De-enrichment, de-conversion, loans, swaps, interchanges and other new kinds of transactions have proliferated. These changes in market structure and market mechanisms have been accompanied by substantial changes in price formation, that is the process by which market price is set. Today, the level and direction of price are set in a trading dominated spot market environment, fuelled by inventory liquidation and Soviet and other non-traditional supply. (author)

  5. Complexity of formation in holography

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, Shira [Perimeter Institute for Theoretical Physics,Waterloo, ON N2L 2Y5 (Canada); Marrochio, Hugo [Perimeter Institute for Theoretical Physics,Waterloo, ON N2L 2Y5 (Canada); Department of Physics & Astronomy and Guelph-Waterloo Physics Institute,University of Waterloo, Waterloo, ON N2L 3G1 (Canada); Myers, Robert C. [Perimeter Institute for Theoretical Physics,Waterloo, ON N2L 2Y5 (Canada)

    2017-01-16

    It was recently conjectured that the quantum complexity of a holographic boundary state can be computed by evaluating the gravitational action on a bulk region known as the Wheeler-DeWitt patch. We apply this complexity=action duality to evaluate the ‘complexity of formation’ (DOI: 10.1103/PhysRevLett.116.191301; 10.1103/PhysRevD.93.086006), i.e. the additional complexity arising in preparing the entangled thermofield double state with two copies of the boundary CFT compared to preparing the individual vacuum states of the two copies. We find that for boundary dimensions d>2, the difference in the complexities grows linearly with the thermal entropy at high temperatures. For the special case d=2, the complexity of formation is a fixed constant, independent of the temperature. We compare these results to those found using the complexity=volume duality.

  6. Uranium price formation. Final report

    International Nuclear Information System (INIS)

    1977-10-01

    The modern uranium industry came into existence in 1946. Until 1966, its sole customer was the Atomic Energy Commission, whose needs for U 3 O 8 relative to industry capacity declined over the years. The development of the commercial market after 1965 coincided with a period of excess capacity and falling nominal and real prices. Gradually in 1973 and dramatically thereafter, market conditions changed and prices rose as utilities sought larger quantities of U 3 O 8 and longer term contracts. Questions about availability of long-run supplies were raised, given the known reserve base. The response of the supply of U 3 O 8 to incentives offered first by the AEC and later by the utilities in the context of new and developing market conventions is examined. The methodology used is microeconomic analysis, qualitatively applied to the history of price formation in the market. Because the study emphasizes the implications of the history of uranium price formation for forecasting supply response, the study presents many different kinds of data and evaluates their quality and appropriateness for forecasting. A simple, very-useful framework for analyzing the history of the market for U 3 O 8 was developed and used to describe supply responses in selected important periods of the industry's development. It is concluded that the response of supply of U 3 O 8 to rising prices or to expectations of demand growth has been impressively strong. The potential reserve inventory is large enough to meet the needs for nuclear power generation through the end of this century. The price necessary to induce producers to find and produce these reserves is uncertain, partly because of problems inherent in estimating long-run supply curves and partly because recent inflation has created major uncertainties about the cost of future supplies

  7. Thermal Behaviour of clay formations

    International Nuclear Information System (INIS)

    Tassoni, E.

    1985-01-01

    The programme carried out by ENEA to model the thermal-hydraulic-mechanical behaviour of the clay formations and to measure, in situ and in laboratory, the thermal properties of these rocks, is presented. An in situ heating experiment has been carried out in an open clay quarry in the area of Monterotondo, near Rome. The main goal of the experiment was to know the temperature field and the thermal effects caused by the high level radioactive waste disposed of in a clayey geological formation. The conclusions are as follows: - the thermal conduction codes are sufficiently accurate to forecast the temperature increases caused in the clay by the dissipation of the heat generated by high level radioactive waste; - the thermal conductivity deduced by means of the ''curve fitting'' method ranges from 0.015 to 0.017 W.cm -1 . 0 C -1 - the temperature variation associated with the transport of clay interstitial water caused by temperature gradient is negligible. A laboratory automated method has been designed to measure the thermal conductivity and diffusivity in clay samples. A review of experimental data concerning thermomechanical effects in rocks as well as results of thermal experiments performed at ISMES on clays are presented. Negative thermal dilation has been found both in the elastic and plastic range under constant stress. Thermoplastic deformation appears ten times greater than the thermoelastic one. A mathematical model is proposed in order to simulate the above and other effects that encompass thermal-elastic-plastic-pore water pressure response of clays at high temperature and effective pressure with undrained and transient drainage conditions. Implementation of the two versions into a finite element computer code is described

  8. Drill cuttings mount formation study

    Science.gov (United States)

    Teh, Su Yean; Koh, Hock Lye

    2014-07-01

    Oil, Gas and Energy sector has been identified as an essential driving force in the Malaysian Economic Transformation Programs (ETP). Recently confirmed discovery of many offshore oil and gas deposits in Malaysian waters has ignited new confidence in this sector. However, this has also spurred intense interest on safeguarding the health and environment of coastal waters in Malaysia from adverse impact resulting from offshore oil and gas production operation. Offshore discharge of spent drilling mud and rock cuttings is the least expensive and simplest option to dispose of large volumes of drilling wastes. But this onsite offshore disposal may have adverse environmental impacts on the water column and the seabed. It may also pose occupational health hazards to the workers living in the offshore platforms. It is therefore important to model the transport and deposition of drilling mud and rock cuttings in the sea to enable proper assessment of their adverse impacts on the environment and the workers. Further, accumulation of drill particles on the seabed may impede proper operation of pipelines on the seabed. In this paper, we present an in-house application model TUNA-PT developed to cater to local oil and gas industry needs to simulate the dispersion and mount formation of drill cuttings by offshore oil and gas exploration and production platforms. Using available data on Malaysian coastal waters, simulation analyses project a pile formation on the seabed with a maximum height of about 1 m and pile radius of around 30 to 50 m. Simulated pile heights are not sensitive to the heights of release of the cuttings as the sensitivity has been mitigated by the depth of water.

  9. Engram Formation in Psychiatric Disorders

    Directory of Open Access Journals (Sweden)

    Peter J. Gebicke-Haerter

    2014-05-01

    Full Text Available Environmental factors substantially influence beginning and progression of mental illness, reinforcing or reducing the consequences of genetic vulnerability. Often initiated by early traumatic events, engrams or memories are formed that may give rise to a slow and subtle progression of psychiatric disorders. The large delay between beginning and time of onset (diagnosis may be explained by efficient compensatory mechanisms observed in brain metabolism that use optional pathways in highly redundant molecular interactions.To this end, research has to deal with mechanisms of learning and long-term memory formation, which involves a epigenetic changes, b altered neuronal activities and c changes in neuron-glia communication. On the epigenetic level, apparently DNA-methylations are more stable than histone modifications, although both closely interact. Neuronal activities basically deliver digital information, which clearly can serve as basis for memory formation (LTP. However, research in this respect has long time neglected the importance of glia. They are more actively involved in the control of neuronal activities than thought before. They can both reinforce and inhibit neuronal activities by transducing neuronal information from frequency-encoded to amplitude and frequency-modulated calcium wave patterns spreading in the glial syncytium by use of gap junctions. In this way, they serve integrative functions. In conclusion, we are dealing with two concepts of encoding information that mutually control each other and synergize: a digital (neuronal and a wave-like (glial computing, forming neuron-glia functional units with inbuilt feedback loops to maintain balance of excitation and inhibition. To better understand mental illness, we have to gain more insight into the dynamics of adverse environmental impact on those cellular and molecular systems. This report summarizes existing knowledge and draws some outline about further research in molecular

  10. Heating tar sands formations while controlling pressure

    Science.gov (United States)

    Stegemeier, George Leo [Houston, TX; Beer, Gary Lee [Houston, TX; Zhang, Etuan [Houston, TX

    2010-01-12

    Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. A pressure in the majority of the section may be maintained below a fracture pressure of the formation. The pressure in the majority of the section may be reduced to a selected pressure after the average temperature reaches a temperature that is above 240.degree. C. and is at or below pyrolysis temperatures of hydrocarbons in the section. At least some hydrocarbon fluids may be produced from the formation.

  11. Radiogeochemical features of hydrothermal metasomatic formations

    International Nuclear Information System (INIS)

    Plyushchev, E.V.; Ryabova, L.A.; Shatov, V.V.

    1978-01-01

    Considered are the most general peculiarities of uranium and thorium distributions in hydrothermal-metasomatic formations of three levels of substance formation: 1) in hydrothermal minerals; 2) in natural associations of these minerals (in the altered rocks, metasomatites, ores, etc.); 3) ordened series of zonally and in stage conjugated hydrothermal-metasomatic formations. Statistically stable recurrence of natural combinations of hydrothermal-metasomatic formations points out conjugation of their formation in the directed evolution in the general hydrothermal process. Series of metasomatic formations, the initial members of which are potassium metasomatites, mostly result in accumulation up to industrial concentrations of radioactive elements in final members of these formations. Development of midlow-temperature propylitic alterations in highly radiative rocks causes the same accumulation

  12. Improving the Formatting Tools of CDS Invenio

    CERN Document Server

    Caffaro, J; Pu Faltings, Pearl

    2006-01-01

    CDS Invenio is the web-based integrated digital library system developed at CERN. It is a strategical tool that supports the archival and open dissemination of documents produced by CERN researchers. This paper reports on my Master’s thesis work done on BibFormat, a module in CDS Invenio, which formats documents metadata. The goal of this project was to implement a completely new formatting module for CDS Invenio. In this report a strong emphasis is put on the user-centered design of the new BibFormat. The bibliographic formatting process and its requirements are discussed. The task analysis and its resulting interaction model are detailed. The document also shows the implemented user interface of BibFormat and gives the results of the user evaluation of this interface. Finally the results of a small usability study of the formats included in CDS Invenio are discussed.

  13. Fibril formation from pea protein and subsequent gel formation.

    Science.gov (United States)

    Munialo, Claire Darizu; Martin, Anneke H; van der Linden, Erik; de Jongh, Harmen H J

    2014-03-19

    The objective of this study was to characterize fibrillar aggregates made using pea proteins, to assemble formed fibrils into protein-based gels, and to study the rheological behavior of these gels. Micrometer-long fibrillar aggregates were observed after pea protein solutions had been heated for 20 h at pH 2.0. Following heating of pea proteins, it was observed that all of the proteins were hydrolyzed into peptides and that 50% of these peptides were assembled into fibrils. Changes on a structural level in pea proteins were studied using circular dichroism, transmission electron microscopy, and particle size analysis. During the fibril assembly process, an increase in aggregate size was observed, which coincided with an increase in thioflavin T binding, indicating the presence of β-sheet aggregates. Fibrils made using pea proteins were more branched and curly. Gel formation of preformed fibrils was induced by slow acidification from pH 7.0 to a final pH of around pH 5.0. The ability of pea protein-based fibrillar gels to fracture during an amplitude sweep was comparable to those of soy protein and whey protein-based fibrillar gels, although gels prepared from fibrils made using pea protein and soy protein were weaker than those of whey protein. The findings show that fibrils can be prepared from pea protein, which can be incorporated into protein-based fibrillar gels.

  14. Magnetic Assisted Colloidal Pattern Formation

    Science.gov (United States)

    Yang, Ye

    Pattern formation is a mysterious phenomenon occurring at all scales in nature. The beauty of the resulting structures and myriad of resulting properties occurring in naturally forming patterns have attracted great interest from scientists and engineers. One of the most convenient experimental models for studying pattern formation are colloidal particle suspensions, which can be used both to explore condensed matter phenomena and as a powerful fabrication technique for forming advanced materials. In my thesis, I have focused on the study of colloidal patterns, which can be conveniently tracked in an optical microscope yet can also be thermally equilibrated on experimentally relevant time scales, allowing for ground states and transitions between them to be studied with optical tracking algorithms. In particular, I have focused on systems that spontaneously organize due to particle-surface and particle-particle interactions, paying close attention to systems that can be dynamically adjusted with an externally applied magnetic or acoustic field. In the early stages of my doctoral studies, I developed a magnetic field manipulation technique to quantify the adhesion force between particles and surfaces. This manipulation technique is based on the magnetic dipolar interactions between colloidal particles and their "image dipoles" that appear within planar substrate. Since the particles interact with their own images, this system enables massively parallel surface force measurements (>100 measurements) in a single experiment, and allows statistical properties of particle-surface adhesion energies to be extracted as a function of loading rate. With this approach, I was able to probe sub-picoNewton surface interactions between colloidal particles and several substrates at the lowest force loading rates ever achieved. In the later stages of my doctoral studies, I focused on studying patterns formed from particle-particle interaction, which serve as an experimental model of

  15. Benzene formation in electronic cigarettes.

    Directory of Open Access Journals (Sweden)

    James F Pankow

    Full Text Available The heating of the fluids used in electronic cigarettes ("e-cigarettes" used to create "vaping" aerosols is capable of causing a wide range of degradation reaction products. We investigated formation of benzene (an important human carcinogen from e-cigarette fluids containing propylene glycol (PG, glycerol (GL, benzoic acid, the flavor chemical benzaldehyde, and nicotine.Three e-cigarette devices were used: the JUULTM "pod" system (provides no user accessible settings other than flavor cartridge choice, and two refill tank systems that allowed a range of user accessible power settings. Benzene in the e-cigarette aerosols was determined by gas chromatography/mass spectrometry. Benzene formation was ND (not detected in the JUUL system. In the two tank systems benzene was found to form from propylene glycol (PG and glycerol (GL, and from the additives benzoic acid and benzaldehyde, especially at high power settings. With 50:50 PG+GL, for tank device 1 at 6W and 13W, the formed benzene concentrations were 1.9 and 750 μg/m3. For tank device 2, at 6W and 25W, the formed concentrations were ND and 1.8 μg/m3. With benzoic acid and benzaldehyde at ~10 mg/mL, for tank device 1, values at 13W were as high as 5000 μg/m3. For tank device 2 at 25W, all values were ≤~100 μg/m3. These values may be compared with what can be expected in a conventional (tobacco cigarette, namely 200,000 μg/m3. Thus, the risks from benzene will be lower from e-cigarettes than from conventional cigarettes. However, ambient benzene air concentrations in the U.S. have typically been 1 μg/m3, so that benzene has been named the largest single known cancer-risk air toxic in the U.S. For non-smokers, chronically repeated exposure to benzene from e-cigarettes at levels such as 100 or higher μg/m3 will not be of negligible risk.

  16. Method of developing thick sloping coal formations

    Energy Technology Data Exchange (ETDEWEB)

    Bragintsev, V F; Mashkovtsev, I L; Semenov, V S; Zykov, V N

    1980-04-25

    A method is patented for developing thick sloping coal formations in 3 inclined layers. It includes conducting developmental operations for each of the layers until one begins the last one and extraction of the layers. In order to improve effectivess and extraction operation safety one first carried out preliminary development of a formation in thin strips beneath protected objects when extracting formation which contain alot of gas. Then one removes the gas of a formation through boreholes that have been drilled into the formation from the indicated workings. Then one works the upper layer in thin strips in a sequence from the roof of the formation to the floor of the upper layer. The one strengthens roof rock of the formation by pumping in a quickly hardening solution into the boreholes which have been drilled into the roof of the formation after processing the upper layer. The middle layer is worked in thin strips in the sequence from the roof to the ground of the middle layer, then the lower layer of the formation is strengthened by pumping in quickly hardening solution into the formation along degasified boreholes and it is worked in thin strips in sequence from the ground of the lower to its roof. Workings are shaped respectively for the middle and lower layers by deepening workings of the upper and middle layers. The layers are worked respectively after finishing displacement of the roof in front of the extraction face of each subsequent extraction of a layer in alternating fashion.

  17. String formation beyond leading colour

    Energy Technology Data Exchange (ETDEWEB)

    Christiansen, Jesper R. [Department of Astronomy and Theoretical Physics, Lund University,Sölvegatan 14, Lund (Sweden); Theoretical Physics, CERN,CH-1211, Geneva 23 (Switzerland); Skands, Peter Z. [Theoretical Physics, CERN,CH-1211, Geneva 23 (Switzerland); School of Physics and Astronomy, Monash University,VIC-3800 (Australia)

    2015-08-03

    We present a new model for the hadronisation of multi-parton systems, in which colour correlations beyond leading N{sub C} are allowed to influence the formation of confining potentials (strings). The multiplet structure of SU(3) is combined with a minimisation of the string potential energy, to decide between which partons strings should form, allowing also for “baryonic” configurations (e.g., two colours can combine coherently to form an anticolour). In e{sup +}e{sup −}collisions, modifications to the leading-colour picture are small, suppressed by both colour and kinematics factors. But in pp collisions, multi-parton interactions increase the number of possible subleading connections, counteracting their naive 1/N{sub C}{sup 2} suppression. Moreover, those that reduce the overall string lengths are kinematically favoured. The model, which we have implemented in the PYTHIA 8 generator, is capable of reaching agreement not only with the important 〈p{sub ⊥}〉(n{sub charged}) distribution but also with measured rates (and ratios) of kaons and hyperons, in both ee and pp collisions. Nonetheless, the shape of their p{sub ⊥} spectra remains challenging to explain.

  18. Galaxy formation and physical bias

    Science.gov (United States)

    Cen, Renyue; Ostriker, Jeremiah P.

    1992-01-01

    We have supplemented our code, which computes the evolution of the physical state of a representative piece of the universe to include, not only the dynamics of dark matter (with a standard PM code), and the hydrodynamics of the gaseous component (including detailed collisional and radiative processes), but also galaxy formation on a heuristic but plausible basis. If, within a cell the gas is Jeans' unstable, collapsing, and cooling rapidly, it is transformed to galaxy subunits, which are then followed with a collisionless code. After grouping them into galaxies, we estimate the relative distributions of galaxies and dark matter and the relative velocities of galaxies and dark matter. In a large scale CDM run of 80/h Mpc size with 8 x 10 exp 6 cells and dark matter particles, we find that physical bias b is on the 8/h Mpc scale is about 1.6 and increases towards smaller scales, and that velocity bias is about 0.8 on the same scale. The comparable HDM simulation is highly biased with b = 2.7 on the 8/h Mpc scale. Implications of these results are discussed in the light of the COBE observations which provide an accurate normalization for the initial power spectrum. CDM can be ruled out on the basis of too large a predicted small scale velocity dispersion at greater than 95 percent confidence level.

  19. Stages of neuronal network formation

    International Nuclear Information System (INIS)

    Woiterski, Lydia; Käs, Josef A; Claudepierre, Thomas; Luxenhofer, Robert; Jordan, Rainer

    2013-01-01

    Graph theoretical approaches have become a powerful tool for investigating the architecture and dynamics of complex networks. The topology of network graphs revealed small-world properties for very different real systems among these neuronal networks. In this study, we observed the early development of mouse retinal ganglion cell (RGC) networks in vitro using time-lapse video microscopy. By means of a time-resolved graph theoretical analysis of the connectivity, shortest path length and the edge length, we were able to discover the different stages during the network formation. Starting from single cells, at the first stage neurons connected to each other ending up in a network with maximum complexity. In the further course, we observed a simplification of the network which manifested in a change of relevant network parameters such as the minimization of the path length. Moreover, we found that RGC networks self-organized as small-world networks at both stages; however, the optimization occurred only in the second stage. (paper)

  20. Dark Energy and Structure Formation

    International Nuclear Information System (INIS)

    Singh, Anupam

    2010-01-01

    We study the gravitational dynamics of dark energy configurations. We report on the time evolution of the dark energy field configurations as well as the time evolution of the energy density to demonstrate the gravitational collapse of dark energy field configurations. We live in a Universe which is dominated by Dark Energy. According to current estimates about 75% of the Energy Density is in the form of Dark Energy. Thus when we consider gravitational dynamics and Structure Formation we expect Dark Energy to play an important role. The most promising candidate for dark energy is the energy density of fields in curved space-time. It therefore become a pressing need to understand the gravitational dynamics of dark energy field configurations. We develop and describe the formalism to study the gravitational collapse of fields given any general potential for the fields. We apply this formalism to models of dark energy motivated by particle physics considerations. We solve the resulting evolution equations which determine the time evolution of field configurations as well as the dynamics of space-time. Our results show that gravitational collapse of dark energy field configurations occurs and must be considered in any complete picture of our universe.

  1. Chloride Transport in Heterogeneous Formation

    Science.gov (United States)

    Mukherjee, A.; Holt, R. M.

    2017-12-01

    The chloride mass balance (CMB) is a commonly-used method for estimating groundwater recharge. Observations of the vertical distribution of pore-water chloride are related to the groundwater infiltration rates (i.e. recharge rates). In CMB method, the chloride distribution is attributed mainly to the assumption of one dimensional piston flow. In many places, however, the vertical distribution of chloride will be influenced by heterogeneity, leading to horizontal movement of infiltrating waters. The impact of heterogeneity will be particularly important when recharge is locally focused. When recharge is focused in an area, horizontal movement of chloride-bearing waters, coupled with upward movement driven by evapotranspiration, may lead to chloride bulges that could be misinterpreted if the CMB method is used to estimate recharge. We numerically simulate chloride transport and evaluate the validity of the CMB method in highly heterogeneous systems. This simulation is conducted for the unsaturated zone of Ogallala, Antlers, and Gatuna (OAG) formations in Andrews County, Texas. A two dimensional finite element model will show the movement of chloride through heterogeneous systems. We expect to see chloride bulges not only close to the surface but also at depths characterized by horizontal or upward movement. A comparative study of focused recharge estimates in this study with available recharge data will be presented.

  2. New Office Software course format!

    CERN Multimedia

    HR Department

    Always keen to anticipate your  training needs, the Technical Training service is pleased to propose two new Office Software course formats: “Focus on... ”:  On a monthly basis we will propose a theme such as “Sharepoint Collaboration Workspace” or “Word 2007” or “charts”, etc.  You will be invited to send us in advance your questions regarding the proposed topic and register  for the course through our Training Catalogue. During the session, our trainer will answer all the questions received and participants will increase their knowledge thanks to the solutions discussed for everyone. The course will last two hours, from 9-00 to 11-00 a.m. - with open questions on the proposed topic at the end.   “Office software Individual coaching”: If one or more specific topics are causing you sleepless nights, you can get the help of our trainer who will ...

  3. New Office Software course format!

    CERN Multimedia

    HR Department

    2009-01-01

    Always keen to anticipate your  training needs, the Technical Training service is pleased to propose two new Office Software course formats: “Focus on... ”:  On a monthly basis we will propose a theme such as “Sharepoint Collaboration Workspace” or “Word 2007” or “charts”, etc.  You will be invited to send us in advance your questions regarding the proposed topic and register  for the course through our Training Catalogue. During the session, our trainer will answer all the questions received and participants will increase their knowledge thanks to the solutions discussed for everyone. The course will last two hours, from 9-00 to 11-00 a.m. - with open questions on the proposed topic at the end.   “Office software Individual coaching”: If one or more specific topics are causing you sleepless nights, you can get the help of our trainer who will ...

  4. Formation of submarine gas hydrates

    Energy Technology Data Exchange (ETDEWEB)

    Soloviev, V.; Ginsburg, G.D. (Reserch Institute of Geology and Mineral Resources of the Ocean ' ' VNII Okeangeologia' ' , St. Petersburg (Russian Federation))

    1994-03-01

    Submarine gas hydrates have been discoverd in the course of deep-sea drilling (DSDP and ODP) and bottom sampling in many offshore regions. This paper reports on expeditions carried out in the Black, Caspian and Okhotsk Seas. Gas hydrate accumulations were discovered and investigated in all these areas. The data and an analysis of the results of the deep-sea drilling programme suggest that the infiltration of gas-bearing fluids is a necessary condition for gas hydrate accumulation. This is confirmed by geological observations at three scale levels. Firstly, hydrates in cores are usually associated with comparatively coarse-grained, permeable sediments as well as voids and fractures. Secondly, hydrate accumulations are controlled by permeable geological structures, i.e. faults, diapirs, mud volcanos as well as layered sequences. Thirdly, in the worldwide scale, hydrate accumulations are characteristic of continental slopes and rises and intra-continental seas where submarine seepages also are widespread. Both biogenic and catagenic gas may occur, and the gas sources may be located at various distances from the accumulation. Gas hydrates presumably originate from water-dissolved gas. The possibility of a transition from dissolved gas into hydrate is confirmed by experimental data. Shallow gas hydrate accumulations associated with gas-bearing fluid plumes are the most convenient features for the study of submarine hydrate formation in general. These accumulations are known from the Black, Caspian and Okhotsk Seas, the Gulf of Mexico and off northern California. (au) (24 refs.)

  5. STAR FORMATION IN DENSE CLUSTERS

    International Nuclear Information System (INIS)

    Myers, Philip C.

    2011-01-01

    A model of core-clump accretion with equally likely stopping describes star formation in the dense parts of clusters, where models of isolated collapsing cores may not apply. Each core accretes at a constant rate onto its protostar, while the surrounding clump gas accretes as a power of protostar mass. Short accretion flows resemble Shu accretion and make low-mass stars. Long flows resemble reduced Bondi accretion and make massive stars. Accretion stops due to environmental processes of dynamical ejection, gravitational competition, and gas dispersal by stellar feedback, independent of initial core structure. The model matches the field star initial mass function (IMF) from 0.01 to more than 10 solar masses. The core accretion rate and the mean accretion duration set the peak of the IMF, independent of the local Jeans mass. Massive protostars require the longest accretion durations, up to 0.5 Myr. The maximum protostar luminosity in a cluster indicates the mass and age of its oldest protostar. The distribution of protostar luminosities matches those in active star-forming regions if protostars have a constant birthrate but not if their births are coeval. For constant birthrate, the ratio of young stellar objects to protostars indicates the star-forming age of a cluster, typically ∼1 Myr. The protostar accretion luminosity is typically less than its steady spherical value by a factor of ∼2, consistent with models of episodic disk accretion.

  6. Shock formation within sonoluminescence bubbles

    International Nuclear Information System (INIS)

    Vuong, V.Q.; Szeri, A.J.; Young, D.A.

    1999-01-01

    A strong case has been made by several authors that sharp, spherically symmetric shocks converging on the center of a spherical bubble driven by a strong acoustic field give rise to rapid compression and heating that produces the brief flash of light known as sonoluminescence. The formation of such shocks is considered. It is found that, although at the main collapse the bubble wall does indeed launch an inwardly-traveling compression wave, and although the subsequent reflection of the wave at the bubble center produces a very rapid temperature peak, the wave is prevented from steepening into a sharp shock by an adverse gradient in the sound speed caused by heat transfer. It is shown that the mathematical characteristics of the flow can be prevented from accumulating into a shock front by this adverse sound speed gradient. A range of results is presented for a variety of bubble ambient radii and sound field amplitudes suggested by experiments. The time scale of the peak temperature in the bubble is set by the dynamics of the compression wave: this is typically in the range 100 - 300 ps (FWHM) in concert with recent measurements of the sonoluminescence pulse width. copyright 1999 American Institute of Physics

  7. Spheromak formation studies in SSPX

    International Nuclear Information System (INIS)

    Hill, D.N.; Bulmer, R.H.; Cohen, B.L.; Hooper, E.B.; LoDestro, L.L.; Mattor, N.; McLean, H.S.; Moller, J.; Pearlstein, L.D.; Ryutov, D.D.; Stallard, B.W.; Wood, R.D.; Woodruff, S.; Holcomb, C.T.; Jarboe, T.; Sovinec, C.R.; Wang, Z.; Wurden, G.

    2000-01-01

    We present results from the Sustained Spheromak Physics Experiment (SSPX) at LLNL, which has been built to study energy confinement in spheromak plasmas sustained for up to 2 ms by coaxial DC helicity injection. Peak toroidal currents as high as 600kA have been obtained in the 1m dia. (0.23m minor radius) device using injection currents between 200-400kA; these currents generate edge poloidal fields in the range of 0.2-0.4T. The internal field and current profiles are inferred from edge field measurements using the CORSICA code. Density and impurity control is obtained using baking, glow discharge cleansing, and titanium gettering, after which long plasma decay times (τ (ge) 1.5ms) are observed and impurity radiation losses are reduced from ∼50% to e (0)∼120eV and β e ∼7%. Edge field measurements show the presence of n=1 modes during the formation phase, as has been observed in other spheromaks. This mode dies away during sustainment and decay so that edge fluctuation levels as low as 1% have been measured. These results are compared with numerical simulations using the NIMROD code

  8. SPMHD simulations of structure formation

    Science.gov (United States)

    Barnes, David J.; On, Alvina Y. L.; Wu, Kinwah; Kawata, Daisuke

    2018-05-01

    The intracluster medium of galaxy clusters is permeated by μ {G} magnetic fields. Observations with current and future facilities have the potential to illuminate the role of these magnetic fields play in the astrophysical processes of galaxy clusters. To obtain a greater understanding of how the initial seed fields evolve to the magnetic fields in the intracluster medium requires magnetohydrodynamic simulations. We critically assess the current smoothed particle magnetohydrodynamic (SPMHD) schemes, especially highlighting the impact of a hyperbolic divergence cleaning scheme and artificial resistivity switch on the magnetic field evolution in cosmological simulations of the formation of a galaxy cluster using the N-body/SPMHD code GCMHD++. The impact and performance of the cleaning scheme and two different schemes for the artificial resistivity switch is demonstrated via idealized test cases and cosmological simulations. We demonstrate that the hyperbolic divergence cleaning scheme is effective at suppressing the growth of the numerical divergence error of the magnetic field and should be applied to any SPMHD simulation. Although the artificial resistivity is important in the strong field regime, it can suppress the growth of the magnetic field in the weak field regime, such as galaxy clusters. With sufficient resolution, simulations with divergence cleaning can reproduce observed magnetic fields. We conclude that the cleaning scheme alone is sufficient for galaxy cluster simulations, but our results indicate that the SPMHD scheme must be carefully chosen depending on the regime of the magnetic field.

  9. Decentralized Control for Scalable Quadcopter Formations

    Directory of Open Access Journals (Sweden)

    Qasim Ali

    2016-01-01

    Full Text Available An innovative framework has been developed for teamwork of two quadcopter formations, each having its specified formation geometry, assigned task, and matching control scheme. Position control for quadcopters in one of the formations has been implemented through a Linear Quadratic Regulator Proportional Integral (LQR PI control scheme based on explicit model following scheme. Quadcopters in the other formation are controlled through LQR PI servomechanism control scheme. These two control schemes are compared in terms of their performance and control effort. Both formations are commanded by respective ground stations through virtual leaders. Quadcopters in formations are able to track desired trajectories as well as hovering at desired points for selected time duration. In case of communication loss between ground station and any of the quadcopters, the neighboring quadcopter provides the command data, received from the ground station, to the affected unit. Proposed control schemes have been validated through extensive simulations using MATLAB®/Simulink® that provided favorable results.

  10. Autonomous Formations of Multi-Agent Systems

    Science.gov (United States)

    Dhali, Sanjana; Joshi, Suresh M.

    2013-01-01

    Autonomous formation control of multi-agent dynamic systems has a number of applications that include ground-based and aerial robots and satellite formations. For air vehicles, formation flight ("flocking") has the potential to significantly increase airspace utilization as well as fuel efficiency. This presentation addresses two main problems in multi-agent formations: optimal role assignment to minimize the total cost (e.g., combined distance traveled by all agents); and maintaining formation geometry during flock motion. The Kuhn-Munkres ("Hungarian") algorithm is used for optimal assignment, and consensus-based leader-follower type control architecture is used to maintain formation shape despite the leader s independent movements. The methods are demonstrated by animated simulations.

  11. Reflections about the mathematics teachers' formation

    Directory of Open Access Journals (Sweden)

    Maria José de Freitas Mendes

    2010-06-01

    Full Text Available This paper brings some reflections about the formation of the math teacher that made part of my marsters paper and that aimed to investigate the process of formation of the math teacher. The focus of this study incided at the contributions of teaching practice in the teacher's formation above the new paradigms of formation, as a professional development and as a reflexive teacher. These reflections, from the learning and teaching process and from the meaning of form a teacher analyse the crisis and the restructuration of the teacher's formation and conclude being necessary that in the graduation courses there's a character more practice to the pedagogical formation, making possible for the future teacher to develop attitudes of autonomy, reflexion and investigation

  12. Formation temperatures of thermogenic and biogenic methane

    Science.gov (United States)

    Stolper, D.A.; Lawson, M.; Davis, C.L.; Ferreira, A.A.; Santos Neto, E. V.; Ellis, G.S.; Lewan, M.D.; Martini, Anna M.; Tang, Y.; Schoell, M.; Sessions, A.L.; Eiler, J.M.

    2014-01-01

    Methane is an important greenhouse gas and energy resource generated dominantly by methanogens at low temperatures and through the breakdown of organic molecules at high temperatures. However, methane-formation temperatures in nature are often poorly constrained. We measured formation temperatures of thermogenic and biogenic methane using a “clumped isotope” technique. Thermogenic gases yield formation temperatures between 157° and 221°C, within the nominal gas window, and biogenic gases yield formation temperatures consistent with their comparatively lower-temperature formational environments (<50°C). In systems where gases have migrated and other proxies for gas-generation temperature yield ambiguous results, methane clumped-isotope temperatures distinguish among and allow for independent tests of possible gas-formation models.

  13. Habit formation, work ethics, and technological progress

    OpenAIRE

    Faria, João Ricardo; León-Ledesma, Miguel A.

    2002-01-01

    Work ethics affects labor supply. This idea is modeled assuming that work is habit forming. This paper introduces working habits in a neoclassical growth model and compares its outcomes with a model without habit formation. In addition, it analyzes the impact of different forms of technical progress. The findings are that i) labor supply in the habit formation case is higher than in the neoclassical case; ii) unlike in the neoclassical case, labor supply in the presence of habit formation wil...

  14. Theoretical Aspects of Enterprise Business Strategy Formation

    OpenAIRE

    Valentinavičius, Stasys

    2009-01-01

    The paper presents interpretations of business strategy concept and analyses strategy planning and formation, models. The concept of business strategy is revised and formulated considering various authors approaches. Analysis of business strategy formation process – steps of development and management, selection of strategy type – is based on presented strategy planning models. The aspects of enterprise business and investment strategy formation, coordination and valuation are analysed. The s...

  15. Formation and behaviour of organic iodine

    International Nuclear Information System (INIS)

    Zilliacus, R.; Koukkar, P.; Karjunen, T.; Sjoevall, H.

    2002-01-01

    The report presents experimental studies on the formation of organic iodine in severe reactor accidents. The analyses were performed to evaluate the amount of alkaline chemical needed for effective pH control of containment water during the accidents. The formation of organic iodine in solutions used in the filtered venting system and the absorption of iodine compounds in the solutions were studied. Experiments for the formation of organic iodine on painted surfaces were also performed. (au)

  16. Transient Exciplex Formation Electron Transfer Mechanism

    OpenAIRE

    Michael G. Kuzmin; Irina V. Soboleva; Elena V. Dolotova

    2011-01-01

    Transient exciplex formation mechanism of excited-state electron transfer reactions is analyzed in terms of experimental data on thermodynamics and kinetics of exciplex formation and decay. Experimental profiles of free energy, enthalpy, and entropy for transient exciplex formation and decay are considered for several electron transfer reactions in various solvents. Strong electronic coupling in contact pairs of reactants causes substantial decrease of activation energy relative to that for c...

  17. Negative ion formation and neutralization processes, (1)

    International Nuclear Information System (INIS)

    Sugiura, Toshio

    1982-01-01

    This review has been made preliminary for the purpose of contribute to the plasma heating by ''negative ion based neutral beam injection'' in the magnetic confinement fusion reactor. A compilation includes the survey of the general processes of negative ion formation, the data of the cross section of H - ion formation and the neutralization of H - ion, and some of new processes of H - ion formation. The data of cross section are mainly experimental, but partly include the results of theoretical calculation. (author)

  18. Mechanism of anticlinal trap formation

    International Nuclear Information System (INIS)

    Kuliev, G.G; Kasimova, S.M; Kulieva, G.Z.

    2002-01-01

    Full text: Geo dynamic development of sedimentary basin in accompanied in different stages by significant changes of stressed states. These changes can cover the upper layers as well as deep inner layers of geological stack. In certain levels, called critical level, in consequence of exhausting the feasibility of slow constant deformation, change of regular structures Equilibrium State and folding formation may occur. In total with horizontal component of geo static pressure and tectonic stress, in both cases these compressive loads may be enough to form folding by means of regular structure Equilibrium State instability loss and change to more stable Equilibrium State with curved structure. In this report there are the results of investigation of given problem within non-classical linearized 3D theoretical geomechanical model. Symmetric and asymmetric forms of change to more stable Equilibrium State when modeling deformed medium in kind of an isotropic and anisotropic material, in case of small elastic deformation were investigated. So, results permit us to conclude that only owing to submersion, different forms of structural curvature may occur in geological stack and that parameters of these structural form-changing are considered more accurate within non-classical linearized 3D geo dynamical model.Analogous results were obtained in case of compressive stress occurrence in consequence of density differentiation of rocks. From the obtains results it follows that Equilibrium State of half-plane in irregular compression proves to be unstable when assigning on free half-plane surface dead as well as tracking loads. The increase of intensity value of different surface loads exerts contrary influence on values of critical loads of stability loss depending on modeling of their character of influence. So, the increase of intensity of dead surface loads leads to decrease, but increase of tracking surface loads leads to increase of equilibrium state loss critical force

  19. STAR FORMATION IN 30 DORADUS

    International Nuclear Information System (INIS)

    De Marchi, Guido; Spezzi, Loredana; Sirianni, Marco; Andersen, Morten; Paresce, Francesco; Panagia, Nino; Mutchler, Max; Whitmore, Bradley C.; Bond, Howard; Beccari, Giacomo; Balick, Bruce; Dopita, Michael A.; Frogel, Jay A.; Calzetti, Daniela; Marcella Carollo, C.; Disney, Michael J.; Hall, Donald N. B.; Holtzman, Jon A.; Kimble, Randy A.; McCarthy, Patrick J.

    2011-01-01

    Using observations obtained with the Wide-Field Camera 3 on board the Hubble Space Telescope, we have studied the properties of the stellar populations in the central regions of 30 Dor in the Large Magellanic Cloud. The observations clearly reveal the presence of considerable differential extinction across the field. We characterize and quantify this effect using young massive main-sequence stars to derive a statistical reddening correction for most objects in the field. We then search for pre-main-sequence (PMS) stars by looking for objects with a strong (>4σ) Hα excess emission and find about 1150 of them over the entire field. Comparison of their location in the Hertzsprung-Russell diagram with theoretical PMS evolutionary tracks for the appropriate metallicity reveals that about one-third of these objects are younger than ∼4 Myr, compatible with the age of the massive stars in the central ionizing cluster R 136, whereas the rest have ages up to ∼30 Myr, with a median age of ∼12 Myr. This indicates that star formation has proceeded over an extended period of time, although we cannot discriminate between an extended episode and a series of short and frequent bursts that are not resolved in time. While the younger PMS population preferentially occupies the central regions of the cluster, older PMS objects are more uniformly distributed across the field and are remarkably few at the very center of the cluster. We attribute this latter effect to photo-evaporation of the older circumstellar disks caused by the massive ionizing members of R 136.

  20. Processes and problems in secondary star formation

    International Nuclear Information System (INIS)

    Klein, R.I.; Whitaker, R.W.; Sandford, M.T. II.

    1984-03-01

    Recent developments relating the conditions in molecular clouds to star formation triggered by a prior stellar generation are reviewed. Primary processes are those that lead to the formation of a first stellar generation. The secondary processes that produce stars in response to effects caused by existing stars are compared and evaluated in terms of the observational data presently available. We discuss the role of turbulence to produce clumpy cloud structures and introduce new work on colliding inter-cloud gas flows leading to non-linear inhomogeneous cloud structures in an intially smooth cloud. This clumpy morphology has important consequences for secondary formation. The triggering processes of supernovae, stellar winds, and H II regions are discussed with emphasis on the consequences for radiation driven implosion as a promising secondary star formation mechanism. Detailed two-dimensional, radiation-hydrodynamic calculations of radiation driven implosion are discussed. This mechanism is shown to be highly efficient in synchronizing the formation of new stars in congruent to 1-3 x 10 4 years and could account for the recent evidence for new massive star formation in several UCHII regions. It is concluded that, while no single theory adequately explains the variety of star formation observed, a uniform description of star formation is likely to involve several secondary processes. Advances in the theory of star formation will require multiple dimensional calculations of coupled processes. The important non-linear interactions include hydrodynamics, radiation transport, and magnetic fields

  1. Processes and problems in secondary star formation

    International Nuclear Information System (INIS)

    Klein, R.I.; Whitaker, R.W.; Sandford, M.T. II

    1985-01-01

    Recent developments relating the conditions in molecular clouds to star formation triggered by a prior stellar generation are reviewed. Primary processes are those that lead to the formation of a first stellar generation. The secondary processes that produce stars in response to effects caused by existing stars are compared and evaluated in terms of observational data presently available. We discuss the role of turbulence to produce clumpy cloud structures and introduce new work on colliding intercloud gas flows leading to nonlinear inhomogeneous cloud structures in an initially smooth cloud. This clumpy morphology has important consequences for secondary formation. The triggering processes of supernovae, stellar winds, and H II regions are discussed with emphasis on the consequences for radiation-driven implosion as a promising secondary star formation mechanism. Detailed two-dimensional, radiation-hydrodynamic calculations of radiation-driven implosion are discussed. This mechanism is shown to be highly efficient in synchronizing the formation of new stars in -- 1-3 x 10/sup 4/ yr and could account for the recent evidence for new massive star formation in several ultracompact H II regions. It is concluded that, while no single theory adequately explains the variety of star formation observed, a uniform description of star formation is likely to involve several secondary processes. Advances in the theory of star formation will require multi-dimensional calculations of coupled processes. Important nonlinear interactions include hydrodynamics, radiation transport, and magnetic fields

  2. Formation of the First Stars and Blackholes

    Science.gov (United States)

    Yoshida, Naoki

    2018-05-01

    Cosmic reionization is thought to be initiated by the first generation of stars and blackholes. We review recent progress in theoretical studies of early structure formation. Cosmic structure formation is driven by gravitational instability of primeval density fluctuations left over from Big Bang. At early epochs, there are baryonic streaming motions with significant relative velocity with respect to dark matter. The formation of primordial gas clouds is typically delayed by the streaming motions, but then physical conditions for the so-called direct collapse blackhole formation are realized in proto-galactic halos. We present a promising model in which intermediate mass blackholes are formed as early as z = 30.

  3. The NeXus data format

    OpenAIRE

    Könnecke, Mark; Akeroyd, Frederick A.; Osborn, Raymond; Peterson, Peter F.; Richter, Tobias; Suzuki, Jiro; Watts, Benjamin; Wintersberger, Eugen; Wuttke, Joachim; Bernstein, Herbert J.; Brewster, Aaron S.; Campbell, Stuart I.; Clausen, Björn; Cottrell, Stephen; Hoffmann, Jens Uwe

    2015-01-01

    NeXus is an effort by an international group of scientists to define a common data exchange and archival format for neutron, X-ray and muon experiments. NeXus is built on top of the scientific data format HDF5 and adds domain-specific rules for organizing data within HDF5 files, in addition to a dictionary of well defined domain-specific field names. The NeXus data format has two purposes. First, it defines a format that can serve as a container for all relevant data associated with a beamlin...

  4. An anti vimentin antibody promotes tube formation

    DEFF Research Database (Denmark)

    Jørgensen, Mathias Lindh; Møller, Carina Kjeldahl; Rasmussen, Lasse

    2017-01-01

    antibody technology, promotes tube formation of endothelial cells in a 2D matrigel assay. By binding vimentin, the antibody increases the tube formation by 21% after 5 hours of incubation. Addition of the antibody directly to cultured endothelial cells does not influence endothelial cell migration...... or proliferation. The enhanced tube formation can be seen for up to 10 hours where after the effect decreases. It is shown that the antibody-binding site is located on the coil 2 domain of vimentin. To our knowledge this is the first study that demonstrates an enhanced tube formation by binding vimentin in a 2D...

  5. Heating systems for heating subsurface formations

    Science.gov (United States)

    Nguyen, Scott Vinh [Houston, TX; Vinegar, Harold J [Bellaire, TX

    2011-04-26

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  6. Heating tar sands formations to visbreaking temperatures

    Science.gov (United States)

    Karanikas, John Michael [Houston, TX; Colmenares, Tulio Rafael [Houston, TX; Zhang, Etuan [Houston, TX; Marino, Marian [Houston, TX; Roes, Augustinus Wilhelmus Maria [Houston, TX; Ryan, Robert Charles [Houston, TX; Beer, Gary Lee [Houston, TX; Dombrowski, Robert James [Houston, TX; Jaiswal, Namit [Houston, TX

    2009-12-22

    Methods for treating a tar sands formation are described herein. Methods may include heating at least a section of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. The heat may be controlled so that at least a majority of the section reaches an average temperature of between 200.degree. C. and 240.degree. C., which results in visbreaking of at least some hydrocarbons in the section. At least some visbroken hydrocarbon fluids may be produced from the formation.

  7. Towards the Rosetta Stone of planet formation

    Directory of Open Access Journals (Sweden)

    Schmidt T.O.B.

    2011-02-01

    Full Text Available Transiting exoplanets (TEPs observed just ~10 Myrs after formation of their host systems may serve as the Rosetta Stone for planet formation theories. They would give strong constraints on several aspects of planet formation, e.g. time-scales (planet formation would then be possible within 10 Myrs, the radius of the planet could indicate whether planets form by gravitational collapse (being larger when young or accretion growth (being smaller when young. We present a survey, the main goal of which is to find and then characterise TEPs in very young open clusters.

  8. New Particle Formation Study Final Campaign Report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, JN; McMurry, PH [University of Minnesota

    2015-01-01

    The scientific foci of the New Particle Formation Study were the formation and evolution of atmospheric aerosols and the impacts of newly formed particles on cloud processes. Specifically, we planned to: (1) to identify the species and mechanisms responsible for the initial steps of new particle formation, i.e., the formation of thermodynamically stable clusters; (2) investigate the role of acid-base chemistry in new particle growth through measurements of ammonia and amines as well as organic and inorganic acids in both atmospheric nanoparticles and the gas phase; (3) investigate the contribution of other surface area or volume-controlled processes to nanoparticle formation and growth; (4) create a comprehensive dataset related to new particle formation and growth that can be used as input for our own thermodynamic models as well as the modeling efforts by our Department of Energy (DOE) Aerosol Life Cycle working group collaborators; (5) characterize the increase of the number and activity of cloud condensation nuclei (CCN) due to particle formation and growth; (6) determine the regional extent of new particle formation to address the role that atmospheric transport plays in determining the impacts, if any, of new particle formation on cloud number and properties.

  9. Hyaline cartilage formation and tumorigenesis of implanted tissues derived from human induced pluripotent stem cells.

    Science.gov (United States)

    Saito, Taku; Yano, Fumiko; Mori, Daisuke; Kawata, Manabu; Hoshi, Kazuto; Takato, Tsuyoshi; Masaki, Hideki; Otsu, Makoto; Eto, Koji; Nakauchi, Hiromitsu; Chung, Ung-il; Tanaka, Sakae

    2015-01-01

    Induced pluripotent stem cells (iPSCs) are a promising cell source for cartilage regenerative medicine. Meanwhile, the risk of tumorigenesis should be considered in the clinical application of human iPSCs (hiPSCs). Here, we report in vitro chondrogenic differentiation of hiPSCs and maturation of the differentiated hiPSCs through transplantation into mouse knee joints. Three hiPSC clones showed efficient chondrogenic differentiation using an established protocol for human embryonic stem cells. The differentiated hiPSCs formed hyaline cartilage tissues at 8 weeks after transplantation into the articular cartilage of NOD/SCID mouse knee joints. Although tumors were not observed during the 8 weeks after transplantation, an immature teratoma had developed in one mouse at 16 weeks. In conclusion, hiPSCs are a potent cell source for regeneration of hyaline articular cartilage. However, the risk of tumorigenesis should be managed for clinical application in the future.

  10. Induced hemocompatibility and bone formation as biological scaffold for cell therapy implant

    Directory of Open Access Journals (Sweden)

    Keng-Liang Ou

    2016-06-01

    Full Text Available Although stem cells can become almost any type of specialized cell in the human body and may have the potential to generate replacement cells for tissues and organs, the transplantation of these cells are hindered by immune rejection and teratoma formation. However, scientists have found a promising solution for these problems-they have discovered the ability to isolate stem cells from a patient’s umbilical cord blood or bone marrow. Even more recently, small stem cells, such as spore-like stem cells, Blastomere-Like Stem Cells (BLSCs, and Very-Small Embryonic-Like stem cells (VSELs isolated directly from the peripheral blood have beeninvestigated as a novel approach to stem cell therapy as they can be isolated directly from the peripheral blood. A newly-discovered population of multipotent stem cells in this class has been dubbed StemBios (SB cells. The potential therapeutic uses of such stem cells have been explored in many ways, one of which includes dental remodeling and construction. Using adult stem cells, scientists have engineered and cultivated teeth in mice that may one day be used for human implantation.It follows that such regeneration may be possible, to a certain degree, in human patients as well. This idea leads to the present study on the effect of SB cell therapy on early osseointegrationof dental implants. Titanium (Ti dental implants have been proven to be a reliable and predictable treatment for restoration of edentulous regions. The osseointegration process can be described in two stages: primary stability (mechanical stability and secondary stability (biological stability. The mechanical stabilization of the implant reflects the interaction between the bone density and the features of the implant designs and can be determined after implant insertion. Alternatively,the biological stabilization of the implant is a physiologic healing process. It is couple to the biological interaction between the external surface of the

  11. Probes of Cosmic Star Formation History

    Indian Academy of Sciences (India)

    I summarize X-ray diagnostic studies of cosmic star formation history in terms of evolutionary schemes for X-ray binary evolution in normal galaxies with evolving star formation. Deep X-ray imaging studies by Chandra and XMM-Newton are now beginning to constrain both the X-ray luminosity evolution of galaxies and the ...

  12. Network Formation under the Threat of Disruption

    NARCIS (Netherlands)

    Hoyer, B.

    2013-01-01

    The studies in this thesis are focused on the impact the presence of a network disruptor has on network formation models. In particular, we build two theoretical models to study the effect of network disruption on network formation and test the effect network disruption has on equilibrium selection

  13. Combinations of partners’ joint venture formation motives

    NARCIS (Netherlands)

    Klijn, E.; Reuer, J.J.; Buckley, P.J.; Glaister, K.W.

    2011-01-01

    Purpose – Prior research on joint venture (JV) formation often examines a single focal firm and assumes it has a single motive for collaboration. This study seeks to investigate how formation motives of partner firms are symmetrically coupled. It considers motives in the context of different

  14. General certification procedure of formation organizations

    CERN Document Server

    Int. At. Energy Agency, Wien

    2002-01-01

    This document presents the procedure dealing with the certification of formation organizations dispensing the formation and the risks prevention to the personnel of A or B category in nuclear facilities. This certification proves the organization ability to satisfy the ''F'' specification of the CEFRI. (A.L.B.)

  15. Problems of Kazakh Literary Criticism Formation

    Directory of Open Access Journals (Sweden)

    Zhandos Smagulov

    2013-01-01

    Full Text Available Тhe article is concerned with the problem of scientific research of Kazakh literature formation in national science. Kazakh literature, having long history of formation is classified by periods. Besides, the article thoroughly considers the principles of the study of methodology, theory, history of spiritual heritage in Kazakh literary criticism

  16. The early ISM and galaxy formation

    Science.gov (United States)

    White, Simon D. M.

    1990-01-01

    Current ideas about galaxy formation are reviewed, with particular attention to when and how it occurred, and what it might have looked like. It is argued that galaxy formation is more recent than originally predicted. Suggestions are presented as to how current observations of distant objects may be interpreted within the cold dark matter theory for the origin of structure.

  17. 25 CFR 82.6 - Petition format.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Petition format. 82.6 Section 82.6 Indians BUREAU OF... REORGANIZED UNDER FEDERAL STATUTE AND OTHER ORGANIZED TRIBES § 82.6 Petition format. Petitions may consist of... of a petition must set forth at least a summary of the objectives of the petitioners and must show...

  18. A Decentralized Approach to Formation Flight Routing

    NARCIS (Netherlands)

    Visser, H.G.; Lopes dos Santos, Bruno F.; Verhagen, C.M.A.

    2016-01-01

    This paper describes the development of an optimization-based cooperative planning system for the efficient routing and scheduling of flight formations. This study considers the use of formation flight as a means to reduce the overall fuel consumption of civil aviation in long-haul operations. It

  19. Unit Monitors Manchester-Format Data Buses

    Science.gov (United States)

    Amador, Jose J.

    1994-01-01

    Circuit card converts data signals into convenient hexadecimal form for troubleshooting. Bus-monitoring unit converts data signals from Manchester II format used on data bus into hexadecimal format. Monitoring circuit causes hexadecimal words to display on video terminal, where test engineer compares them with hexadecimal records for troubleshooting. Circuit monitors one bus or two buses simultaneously.

  20. Distributed formation control for autonomous robots

    NARCIS (Netherlands)

    Garcia de Marina Peinado, Hector Jesús

    2016-01-01

    This thesis addresses several theoretical and practical problems related to formation-control of autonomous robots. Formation-control aims to simultaneously accomplish the tasks of forming a desired shape by the robots and controlling their coordinated collective motion. This kind of robot