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Sample records for escape thymic negative

  1. Models of Aire-dependent gene regulation for thymic negative selection

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    Dina eDanso-Abeam

    2011-05-01

    Full Text Available Mutations in the Autoimmune Regulator (AIRE gene lead to Autoimmune Polyendocrinopathy Syndrome type 1 (APS1, characterized by the development of multi-organ autoimmune damage. The mechanism by which defects in AIRE result in autoimmunity has been the subject of intense scrutiny. At the cellular level, the working model explains most of the clinical and immunological characteristics of APS1, with AIRE driving the expression of tissue restricted antigens (TRAs in the epithelial cells of the thymic medulla. This TRA expression results in effective negative selection of TRA-reactive thymocytes, preventing autoimmune disease. At the molecular level, the mechanism by which AIRE initiates TRA expression in the thymic medulla remains unclear. Multiple different models for the molecular mechanism have been proposed, ranging from classical transcriptional activity, to random induction of gene expression, to epigenetic tag recognition effect, to altered cell biology. In this review, we evaluate each of these models and discuss their relative strengths and weaknesses.

  2. Buying to blunt negative feelings : Materialistic escape from the self

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    Donnelly, Grant E.; Ksendzova, Masha; Howell, Ryan T.; Vohs, Kathleen D.; Baumeister, Roy F.

    2016-01-01

    We propose that escape theory, which describes how individuals seek to free themselves from aversive states of self-awareness, helps explain key patterns of materialistic people's behavior. As predicted by escape theory, materialistic individuals may feel dissatisfied with their standard of living,

  3. Impaired progenitor cell function in HIV-negative infants of HIV-positive mothers results in decreased thymic output and low CD4 counts

    DEFF Research Database (Denmark)

    Nielsen, S. D.; Jeppesen, D. L.; Kolte, L.

    2001-01-01

    and fetal thymic organ cultures (FTOCs). Lower naive CD4 counts (459.3 +/- 68.9 vs 1128.9 +/- 146.8 cells/microL, P mothers were found (frequency of CD4(+) cells with TRECs was 3.6% +/- 0.7% compared with 14.3% +/- 2.2% in controls, P ...). In combination with lower red blood cell counts in infants of HIV-positive mothers, this finding suggested impairment of progenitor cell function. Indeed, progenitors from infants of HIV-positive mothers had decreased cloning efficiency (15.7% +/- 2.6% vs 55.8% +/- 15.9%, P =.009) and seemed to generate fewer T...... cells in FTOCs. In conclusion, lower numbers of naive CD4(+) cells and reduced thymic output in HIV-negative infants of HIV-positive mothers may be due to impaired progenitor cell function....

  4. MODELS OF COVARIANCE FUNCTIONS OF GAUSSIAN RANDOM FIELDS ESCAPING FROM ISOTROPY, STATIONARITY AND NON NEGATIVITY

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    Pablo Gregori

    2014-03-01

    Full Text Available This paper represents a survey of recent advances in modeling of space or space-time Gaussian Random Fields (GRF, tools of Geostatistics at hand for the understanding of special cases of noise in image analysis. They can be used when stationarity or isotropy are unrealistic assumptions, or even when negative covariance between some couples of locations are evident. We show some strategies in order to escape from these restrictions, on the basis of rich classes of well known stationary or isotropic non negative covariance models, and through suitable operations, like linear combinations, generalized means, or with particular Fourier transforms.

  5. Internet Game Addiction, Depression, and Escape From Negative Emotions in Adulthood: A Nationwide Community Sample of Korea.

    Science.gov (United States)

    Kim, Dong Jun; Kim, Kiwon; Lee, Hae-Woo; Hong, Jin-Pyo; Cho, Maeng Je; Fava, Maurizio; Mischoulon, David; Heo, Jung-Yoon; Jeon, Hong Jin

    2017-07-01

    The aim of this study was to investigate the association between adult Internet game addiction (IGA) and mental disorders. A total of 1401 adults aged between 18 and 74 years participated in this study. The IGA group had significantly younger patients, and it showed a higher proportion of unmarried and unemployed adults, and higher rates of suicidal ideation, plan, and attempt than the non-IGA group. Multivariate logistic regression indicated that IGA was significantly associated with major depressive disorder, dysthymia, and depressive disorders adjusting for all variables. The Patient Health Questionnaire-9 score was significantly higher in the IGA group than in the non-IGA group for both young adults and middle groups. "Escape from negative emotions like nervousness, sadness, and anger" was the only significant item associated with depression among symptoms of IGA. This study suggests that adults with IGA and depression may use Internet games to escape from negative emotions.

  6. Significance of thymic scintigraphy

    International Nuclear Information System (INIS)

    Baba, Hiromi; Oshiumi, Yoshihiko; Nakayama, Chikashi; Morita, Kazunori; Koga, Ichinari

    1978-01-01

    Thymic scintigraphy by 67 Ga-citrate and 75 Se-methionine was done on 6 cases of thymoma, and 5 cases of myasthenia gravis. Scan was positive on 5 of 6 cases of thymoma. All patients with malignant thymoma were positive. Among the 7 cases of myasthenia gravis, scintigrams revealed 2 thymomas and 1 hyperplasia on whom no thymic mass suspected. Thymic scintigraphy is useful examination when dealing with myasthenia gravis. (auth.)

  7. Cystic thymic diseases: CT manifestations

    International Nuclear Information System (INIS)

    Song, Soon Young; Choi, Yo Won; Jeon, Eui Yong; Jeon, Seok Chol; Seo, Heung Suk; Hahm, Chang Kok

    1995-01-01

    To describe CT findings and differential points of cystic thymic lesions. We evaluated retrospectively total 19 masses with well marginated cystic lesions at thymic area on CT scans. They were 10 teratomas, 3 congenital thymic cysts, 2 multilocular thymic cysts(associated with thymoma and myasthenia gravis in each), 2 cysts Assciated with thymic Hodgkin's lymphomas an ectopic parathyroid cyst, and an infected thymic cyst. The radiological abnormalities evaluated were thickness of the wall, presence or abscene of septa, mural nodule, solid component, calcification and fat component. All three cases of congenital thymic cysts and an ectopic parathyroid cyst appeared as thin-walled unilocular cyst with homogeneous internal density and without identifiable solid component. In multilocular thymic cyst, there were thick wall and solid components(n =2), thick internal septa and calcifications(n = 1). The cysts of teratomas manifested thick walls(n = 9), internal septa(n = 4), calcifications(n = 6), fat components(n = 4), and solid components(n = 4). Cysts in Hodgkin's diseases appeared as multilocular or unilocular and had thick wall and septa without calcification. Infected thymic cyst presented with multilocular cystic mass with identifiable wall and septa, calcification, and solid components. The thymic diseases with cystic lesion include teratomas, congenital thymic cysts, multilocular thymic cysts, parathyroid cyst, and Hodgkin's disease. Congenital thymic cyst and ectopic parathyroid cyst are thin-walled unilocular cystic lesions. Cystic lesions associated with teratoma, Hodgkin's disease, and multilocular thymic cyst are thick-walled cystic lesions with or without solid component

  8. Thymic commitment of regulatory T cells is a pathway of TCR-dependent selection that isolates repertoires undergoing positive or negative selection.

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    Coutinho, A; Caramalho, I; Seixas, E; Demengeot, J

    2005-01-01

    The seminal work of Le Douarin and colleagues (Ohki et al. 1987; Ohki et al. 1988; Salaun et al. 1990; Coutinho et al. 1993) first demonstrated that peripheral tissue-specific tolerance is centrally established in the thymus, by epithelial stromal cells (TEC). Subsequent experiments have shown that TEC-tolerance is dominant and mediated by CD4 regulatory T cells (Treg) that are generated intrathymically by recognition of antigens expressed on TECs (Modigliani et al. 1995; Modigliani et al. 1996a). From these and other observations, in 1996 Modigliani and colleagues derived a general model for the establishment and maintenance of natural tolerance (MM96) (Modigliani et al. 1996b), with two central propositions: (1) T cell receptor (TCR)-dependent sorting of emergent repertoires generates TEC-specific Treg displaying the highest TCR self-affinities below deletion thresholds, thus isolating repertoires undergoing positive and negative selection; (2) Treg are intrathymically committed (and activated) for a unique differentiative pathway with regulatory effector functions. The model explained the embryonic/perinatal time window of natural tolerance acquisition, by developmental programs determining (1) TCR multireactivity, (2) the cellular composition in the thymic stroma (relative abundance of epithelial vs hemopoietic cells), and (3) the dynamics of peripheral lymphocyte pools, built by accumulation of recent thymic emigrants (RTE) that remain recruitable to regulatory functions. We discuss here the MM96 in the light of recent results demonstrating the promiscuous expression of tissue-specific antigens by medullary TECs (Derbinski et al. 2001; Anderson et al. 2002; Gotter et al. 2004) and indicating that Treg represent a unique differentiative pathway (Fontenot et al. 2003; Hori et al. 2003; Khattri et al. 2003), which is adopted by CD4 T cells with high avidity for TEC-antigens (Bensinger et al. 2001; Jordan et al. 2001; Apostolou et al. 2002). In the likelihood that

  9. Cystic thymic diseases: CT manifestations

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    Song, Soon Young; Choi, Yo Won; Jeon, Eui Yong; Jeon, Seok Chol; Seo, Heung Suk; Hahm, Chang Kok [School of Medicine, Hanyang University, Seoul (Korea, Republic of)

    1995-09-15

    To describe CT findings and differential points of cystic thymic lesions. We evaluated retrospectively total 19 masses with well marginated cystic lesions at thymic area on CT scans. They were 10 teratomas, 3 congenital thymic cysts, 2 multilocular thymic cysts(associated with thymoma and myasthenia gravis in each), 2 cysts Assciated with thymic Hodgkin's lymphomas an ectopic parathyroid cyst, and an infected thymic cyst. The radiological abnormalities evaluated were thickness of the wall, presence or abscene of septa, mural nodule, solid component, calcification and fat component. All three cases of congenital thymic cysts and an ectopic parathyroid cyst appeared as thin-walled unilocular cyst with homogeneous internal density and without identifiable solid component. In multilocular thymic cyst, there were thick wall and solid components(n =2), thick internal septa and calcifications(n = 1). The cysts of teratomas manifested thick walls(n = 9), internal septa(n = 4), calcifications(n = 6), fat components(n = 4), and solid components(n = 4). Cysts in Hodgkin's diseases appeared as multilocular or unilocular and had thick wall and septa without calcification. Infected thymic cyst presented with multilocular cystic mass with identifiable wall and septa, calcification, and solid components. The thymic diseases with cystic lesion include teratomas, congenital thymic cysts, multilocular thymic cysts, parathyroid cyst, and Hodgkin's disease. Congenital thymic cyst and ectopic parathyroid cyst are thin-walled unilocular cystic lesions. Cystic lesions associated with teratoma, Hodgkin's disease, and multilocular thymic cyst are thick-walled cystic lesions with or without solid component.

  10. Computed tomography of thymic abnormalities

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    Schnyder, P.; Candardjis, G.

    1987-05-01

    Computed tomographic examinations of 38 patients with surgically and histologically proven diagnosis were reviewed. Twenty subjects (52%) had an invasive thymoma and 16% an hyperplastic thymus. Myasthenia gravis was present in 6 cases (16%) of thymic abnormalities, four (10,5%) with invasive thymoma and two (5%) with thymic hyperplasia. Graves' disease was also present in one case of thymic hyperplasia. We emphasize the contribution of CT to the diagnosis and the prognosis.

  11. Computed tomography of thymic abnormalities

    International Nuclear Information System (INIS)

    Schnyder, P.; Candardjis, G.

    1987-01-01

    Computed tomographic examinations of 38 patients with surgically and histologically proven diagnosis were reviewed. Twenty subjects (52%) had an invasive thymoma and 16% an hyperplastic thymus. Myasthenia gravis was present in 6 cases (16%) of thymic abnormalities, four (10,5%) with invasive thymoma and two (5%) with thymic hyperplasia. Graves' disease was also present in one case of thymic hyperplasia. We emphasize the contribution of CT to the diagnosis and the prognosis. (orig.)

  12. Expression of RAGE and HMGB1 in thymic epithelial tumors, thymic hyperplasia and regular thymic morphology.

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    Moser, Bernhard; Janik, Stefan; Schiefer, Ana-Iris; Müllauer, Leonhard; Bekos, Christine; Scharrer, Anke; Mildner, Michael; Rényi-Vámos, Ferenc; Klepetko, Walter; Ankersmit, Hendrik Jan

    2014-01-01

    Recently, a role of the receptor for advanced glycation endproducts (RAGE) in myasthenia gravis was described. RAGE and its ligand high mobility group box 1 (HMGB1) play key roles in autoimmunity and cancer. To test whether these molecules are involved in patients with thymic abnormalities we applied immunohistochemical analysis in 33 cases of thymic epithelial tumors, comprising 27 thymomas and 6 thymic carcinomas, and 21 nonneoplastic thymuses. Both molecules were detected in neoplastic epithelial cells: RAGE staining was most intense in WHO type B2 thymomas and thymic carcinomas (pB3>thymic carcinoma (pepithelial cells which was found in 50% of myasthenic patients. Furthermore RAGE and HMGB1 were expressed in thymocytes, macrophages, Hassall's corpuscles, thymic medulla, and germinal center cells in myasthenic patients. Immunohistochemistry results were complemented by systemic measurements (immunosorbent assay): serum levels of soluble RAGE were significantly reduced in patients with epithelial tumors (p = 0.008); and in invasive tumors (p = 0.008). Whereas RAGE was equally reduced in thymic hyperplasia and epithelial tumors (p = 0.003), HMGB1 was only elevated in malignancies (p = 0.036). Results were most pronounced in thymic carcinomas. Thus, RAGE and HMGB1 are involved in the (patho-)physiology of thymus, as evidenced by differentiated thymic and systemic expression patterns that may act as diagnostic or therapeutic targets in autoimmune disease and cancer.

  13. Negative compressibility and non-equivalence of two statistical ensembles in the escape transition of a polymer chain

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    Skvortsov, A.M.; Klushin, L.I.; Leermakers, F.A.M.

    2007-01-01

    An end-tethered polymer chain compressed between two pistons undergoes an abrupt transition from a confined coil state to an inhomogeneous flowerlike conformation partially escaped from the gap. This phase transition is first order in the thermodynamic limit of infinitely long chains. A rigorous

  14. Expression of RAGE and HMGB1 in thymic epithelial tumors, thymic hyperplasia and regular thymic morphology.

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    Bernhard Moser

    Full Text Available Recently, a role of the receptor for advanced glycation endproducts (RAGE in myasthenia gravis was described. RAGE and its ligand high mobility group box 1 (HMGB1 play key roles in autoimmunity and cancer. To test whether these molecules are involved in patients with thymic abnormalities we applied immunohistochemical analysis in 33 cases of thymic epithelial tumors, comprising 27 thymomas and 6 thymic carcinomas, and 21 nonneoplastic thymuses. Both molecules were detected in neoplastic epithelial cells: RAGE staining was most intense in WHO type B2 thymomas and thymic carcinomas (pB3>thymic carcinoma (p<0.001. Conversely, HMGB1 cytoplasmic staining intensities were as follows: A and AB (none, B1 (strong, B2 (moderate, B3 and thymic carcinoma (weak; (p<0.001. Fetal thymic tissue showed a distinct expression of RAGE and HMGB1 in subcapsular cortical epithelial cells which was found in 50% of myasthenic patients. Furthermore RAGE and HMGB1 were expressed in thymocytes, macrophages, Hassall's corpuscles, thymic medulla, and germinal center cells in myasthenic patients. Immunohistochemistry results were complemented by systemic measurements (immunosorbent assay: serum levels of soluble RAGE were significantly reduced in patients with epithelial tumors (p = 0.008; and in invasive tumors (p = 0.008. Whereas RAGE was equally reduced in thymic hyperplasia and epithelial tumors (p = 0.003, HMGB1 was only elevated in malignancies (p = 0.036. Results were most pronounced in thymic carcinomas. Thus, RAGE and HMGB1 are involved in the (patho-physiology of thymus, as evidenced by differentiated thymic and systemic expression patterns that may act as diagnostic or therapeutic targets in autoimmune disease and cancer.

  15. PPARgamma Deficiency Counteracts Thymic Senescence

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    David Ernszt

    2017-11-01

    Full Text Available Thymic senescence contributes to increased incidence of infection, cancer and autoimmunity at senior ages. This process manifests as adipose involution. As with other adipose tissues, thymic adipose involution is also controlled by PPARgamma. This is supported by observations reporting that systemic PPARgamma activation accelerates thymic adipose involution. Therefore, we hypothesized that decreased PPARgamma activity could prevent thymic adipose involution, although it may trigger metabolic adverse effects. We have confirmed that both human and murine thymic sections show marked staining for PPARgamma at senior ages. We have also tested the thymic lobes of PPARgamma haplo-insufficient and null mice. Supporting our working hypothesis both adult PPARgamma haplo-insufficient and null mice show delayed thymic senescence by thymus histology, thymocyte mouse T-cell recombination excision circle qPCR and peripheral blood naive T-cell ratio by flow-cytometry. Delayed senescence showed dose–response with respect to PPARgamma deficiency. Functional immune parameters were also evaluated at senior ages in PPARgamma haplo-insufficient mice (null mice do not reach senior ages due to metabolic adverse affects. As expected, sustained and elevated T-cell production conferred oral tolerance and enhanced vaccination efficiency in senior PPARgamma haplo-insufficient, but not in senior wild-type littermates according to ELISA IgG measurements. Of note, humans also show increased oral intolerance issues and decreased protection by vaccines at senior ages. Moreover, PPARgamma haplo-insufficiency also exists in human known as a rare disease (FPLD3 causing metabolic adverse effects, similar to the mouse. When compared to age- and metabolic disorder-matched other patient samples (FPLD2 not affecting PPARgamma activity, FPLD3 patients showed increased human Trec (hTrec values by qPCR (within healthy human range suggesting delayed thymic senescence, in accordance with

  16. CT findings of thymic tumors

    International Nuclear Information System (INIS)

    Chung, Ho Son; Lee, Sang Jin; Hwang, Mi Soo; Cho, Kil Ho; Chang, Jae Chun; Park, Bok Hwan

    1991-01-01

    A CT scan can make accurate diagnoses of most thymic masses by assessing their size, shape, and internal architecture and is especially effective in detecting pleural implants, mediastinal involvement, and pulmonary parenchymal invasion in malignant thymoma. The authors analyzed the CT findings of 10 histologically-proven thymic masses from 1983 to 1990 in Yeungnam University Hospital. There were 10 cases of thymic masses in the anterior mediastinum consisting of 6 benign, 3 invasive thymomas, and one thymolipoma, while myasthenia gravis was associated with 2 cases of benign thymomas and with one case of invasive thymomas. The CT findings of the benign thymomas (6 cases) were well-defined, bordered, round-or oval-shaped masses with a well-preserved fat plane between the thymic mass and mediastinal great vessels, with no evidence of pleural implants and lung parenchymal invasion. The CT findings of the invasive thymomas (3 cases) were irregular, marginated lobular masses with obliteration of the fat plane between the thymic mass and surrounding great vessels, with evidence of local invasion such as extension to A-P window and mass effect to bronchus. Irregular pleural thickening due to pleural metastasis, multiple metastatic lung parenchymal nodules, and multiple mediastinal lymph node enlargement were also seen in the invasive thymomas. One case of thymolipoma showed an approximately 20cm-size, well-defined fat density mass containing internal septations

  17. CT findings of thymic tumors

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    Chung, Ho Son; Lee, Sang Jin; Hwang, Mi Soo; Cho, Kil Ho; Chang, Jae Chun; Park, Bok Hwan [College of Medicine, Yeungnam University, Daegu (Korea, Republic of)

    1991-05-15

    A CT scan can make accurate diagnoses of most thymic masses by assessing their size, shape, and internal architecture and is especially effective in detecting pleural implants, mediastinal involvement, and pulmonary parenchymal invasion in malignant thymoma. The authors analyzed the CT findings of 10 histologically-proven thymic masses from 1983 to 1990 in Yeungnam University Hospital. There were 10 cases of thymic masses in the anterior mediastinum consisting of 6 benign, 3 invasive thymomas, and one thymolipoma, while myasthenia gravis was associated with 2 cases of benign thymomas and with one case of invasive thymomas. The CT findings of the benign thymomas (6 cases) were well-defined, bordered, round-or oval-shaped masses with a well-preserved fat plane between the thymic mass and mediastinal great vessels, with no evidence of pleural implants and lung parenchymal invasion. The CT findings of the invasive thymomas (3 cases) were irregular, marginated lobular masses with obliteration of the fat plane between the thymic mass and surrounding great vessels, with evidence of local invasion such as extension to A-P window and mass effect to bronchus. Irregular pleural thickening due to pleural metastasis, multiple metastatic lung parenchymal nodules, and multiple mediastinal lymph node enlargement were also seen in the invasive thymomas. One case of thymolipoma showed an approximately 20cm-size, well-defined fat density mass containing internal septations.

  18. Gallium 67 uptake in thymic rebound

    International Nuclear Information System (INIS)

    Hurst, R.; Sabio, H.; Teates, C.D.

    1988-01-01

    We have reported a case of localized thymic enlargement and uptake of gallium 67 in a child who had received antineoplastic chemotherapy. The enlarged thymus showed normal histology, a picture consistent with thymic rebound after nonspecific stress. This case further demonstrates the need to consider thymic rebound as a cause of gallium 67 uptake in children with neoplastic diseases

  19. Thymic hyperplasia in Graves′ disease

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    Narendra Kotwal

    2013-01-01

    Full Text Available Graves′ disease is an autoimmune thyroid condition characterized by the production of autoantibodies against the thyrotropin receptor. It is known to be associated with autoimmune conditions such as myasthenia gravis, Addison′s disease, type 1 diabetes mellitus, and vitiligo. We present a case of rare autoimmune association of Graves′ disease with thymic hyperplasia which regressed after treatment with antithyroid drugs. Exact pathophysiology of thymic hyperplasia in Graves′ is not well understood; it is likely to be the result of rather than the cause of Graves′ disease.

  20. Acquisition of a CD19-negative myeloid phenotype allows immune escape of MLL-rearranged B-ALL from CD19 CAR-T-cell therapy.

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    Gardner, Rebecca; Wu, David; Cherian, Sindhu; Fang, Min; Hanafi, Laïla-Aïcha; Finney, Olivia; Smithers, Hannah; Jensen, Michael C; Riddell, Stanley R; Maloney, David G; Turtle, Cameron J

    2016-05-19

    Administration of lymphodepletion chemotherapy followed by CD19-specific chimeric antigen receptor (CAR)-modified T cells is a remarkably effective approach to treating patients with relapsed and refractory CD19(+) B-cell malignancies. We treated 7 patients with B-cell acute lymphoblastic leukemia (B-ALL) harboring rearrangement of the mixed lineage leukemia (MLL) gene with CD19 CAR-T cells. All patients achieved complete remission (CR) in the bone marrow by flow cytometry after CD19 CAR-T-cell therapy; however, within 1 month of CAR-T-cell infusion, 2 of the patients developed acute myeloid leukemia (AML) that was clonally related to their B-ALL, a novel mechanism of CD19-negative immune escape. These reports have implications for the management of patients with relapsed and refractory MLL-B-ALL who receive CD19 CAR-T-cell therapy. © 2016 by The American Society of Hematology.

  1. Bacillus Calmette-Guérin vaccination, thymic size, and thymic output in healthy newborns

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    Birk, Nina Marie; Nissen, Thomas Nørrelykke; Zingmark, Vera

    2017-01-01

    Background: The Bacillus Calmette-Guérin vaccine (BCG) has been associated with beneficial nonspecific effects on infant health. We aimed to examine the effect of BCG at birth on thymic size and the associations between thymic output, circulating lymphocytes, risk of infection, and thymic size...... with a large thymic size at birth. Conclusion: We found no effect of BCG vaccination on thymic size. The positive association between thymic output, lymphocytes, reduced risk of infections, and TI/TWI suggests that assessment of TI/TWI by ultrasound may be a predictor of the immunological capacity...... in the newborn....

  2. Pubertal Escape From Estradiol Negative Feedback in Ewe Lambs Is Not Accounted for by Decreased ESR1 mRNA or Protein in Kisspeptin Neurons.

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    Bedenbaugh, Michelle N; D'Oliveira, Marcella; Cardoso, Rodolfo C; Hileman, Stanley M; Williams, Gary L; Amstalden, Marcel

    2018-01-01

    In this study, we investigated whether decreased sensitivity to estradiol negative feedback is associated with reduced estrogen receptor α (ESR1) expression in kisspeptin neurons as ewe lambs approach puberty. Lambs were ovariectomized and received no implant (OVX) or an implant containing estradiol (OVX+E). In the middle arcuate nucleus (mARC), ESR1 messenger RNA (mRNA) was greater in OVX than OVX+E lambs but did not differ elsewhere. Post hoc analysis of luteinizing hormone (LH) secretion from OVX+E lambs revealed three patterns of LH pulsatility: low [1 to 2 pulses per 12 hours; low frequency (LF), n = 3], moderate [6 to 7 pulses per 12 hours; moderate frequency (MF), n = 6], and high [>10 pulses per 12 hours; high frequency (HF), n = 5]. The percentage of kisspeptin neurons containing ESR1 mRNA in the preoptic area did not differ among HF, MF, or LF groups. However, the percentage of kisspeptin neurons containing ESR1 mRNA in the mARC was greater in HF (57%) than in MF (36%) or LF (27%) lambs and did not differ from OVX (50%) lambs. A higher percentage of kisspeptin neurons contained ESR1 protein in all regions of the arcuate nucleus (ARC) in OVX compared with OVX+E lambs. There were no differences in ESR1 protein among the HF, MF, or LF groups in the preoptic area or ARC. Contrary to our hypothesis, increases in LH pulsatility were associated with enhanced ESR1 mRNA abundance in kisspeptin neurons in the ARC, and absence of estradiol increased the percentage of kisspeptin neurons containing ESR1 protein in the ARC. Therefore, changes in the expression of ESR1, particularly in kisspeptin neurons in the ARC, do not explain the pubertal escape from estradiol negative feedback in ewe lambs. Copyright © 2018 Endocrine Society.

  3. Bacillus Calmette-Guérin vaccination, thymic size, and thymic output in healthy newborns

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    Birk, Nina Marie; Nissen, Thomas Nørrelykke; Zingmark, Vera

    2017-01-01

    BACKGROUND: The Bacillus Calmette-Guérin vaccine (BCG) has been associated with beneficial nonspecific effects on infant health. We aimed to examine the effect of BCG at birth on thymic size and the associations between thymic output, circulating lymphocytes, risk of infection, and thymic size...... to age 3 mo were parent-reported. RESULTS: BCG vaccination did not affect thymic size at age 3 mo, measured as TI. At birth, the number of lymphocytes, CD4+ T cells, CD8+ T cells, and RTEs were positively associated with TI and TWI. Furthermore, a reduced risk of infections up to age 3 mo was associated...... with a large thymic size at birth. CONCLUSION: We found no effect of BCG vaccination on thymic size. The positive association between thymic output, lymphocytes, reduced risk of infections, and TI/TWI suggests that assessment of TI/TWI by ultrasound may be a predictor of the immunological capacity...

  4. Review of thymic pathology in 30 cats and 36 dogs.

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    Day, M J

    1997-09-01

    Data are presented from 30 cats and 36 dogs in which thymic disease was recognised clinically or on postmortem examination. The diagnoses included thymic lymphoma (19 cats, 12 dogs), thymoma (five cats, 18 dogs), thymic branchial cyst formation or cystic change (one cat, four dogs), thymic hyperplasia (two cats), congenital hypoplasia (one cat, one dog), thymic haemorrhage (one cat, one dog) and thymic amyloidosis (one cat). Thymic lymphoma occurred in younger dogs and cats, and was recorded equally among domestic shorthaired and purebred (especially Siamese) cats. Eight cats with thymic lymphoma were tested for feline leukaemia virus and four were positive. Thymoma occurred more frequently in older cats and dogs, and in Labradors and German shepherd dogs. Thymic tumours were associated with paraneoplastic hypercalcaemia (six dogs), megaoesophagus (two dogs) or interface dermatitis with basement membrane immune complex deposition (one cat). Non-neoplastic thymic diseases were associated with myasthenia gravis (one cat), pemphigus foliaceus (one cat) and superficial necrolytic dermatitis (one cat).

  5. Development of Thymic Epithelial Cells

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    Ulyanchenko, Svetlana; Vaidya, Harsh J.; O'Neill, Kathy E.

    2016-01-01

    The thymus is the primary lymphoid organ in which the T cell repertoire is generated. The complex cellularity of this organ is uniquely designed to facilitate T cell development: defects in thymus development or function can cause immunodeficiencies ranging from the absence of T cell-mediated imm......The thymus is the primary lymphoid organ in which the T cell repertoire is generated. The complex cellularity of this organ is uniquely designed to facilitate T cell development: defects in thymus development or function can cause immunodeficiencies ranging from the absence of T cell......-mediated immunity to broad-spectrum autoimmune disease. Peak thymus size and output occurs early in life, after which the thymus undergoes a natural process of involution. This results in the progressive loss of functional thymus tissue and correspondingly in decreased production of new naïve T cells with age...... - contributing to the diminished capacity of the aged immune system to adequately respond to new antigenic challenge. Age-related thymic involutions, together with the thymic involutions associated with cytotoxic therapies (e.g., radio- or chemotherapy), have raised interest in development of clinically useful...

  6. Thymic epithelial cells. I. Expression of strong suppressive (veto) activity in mouse thymic epithelial cell cultures

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    Claesson, Mogens Helweg; Ropke, C

    1990-01-01

    We show that thymic epithelial cells grown under serum-free conditions in a chemically defined culture medium can act as veto cells in vitro. The veto activity of thymic epithelial cells results in inactivation of specific alloreactive cytotoxic T-cell precursors at the clonal level. It is conclu......We show that thymic epithelial cells grown under serum-free conditions in a chemically defined culture medium can act as veto cells in vitro. The veto activity of thymic epithelial cells results in inactivation of specific alloreactive cytotoxic T-cell precursors at the clonal level...

  7. Thymic Carcinoma Management Patterns among International Thymic Malignancy Interest Group (ITMIG) Physicians with Consensus from the Thymic Carcinoma Working Group.

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    Shepherd, Annemarie; Riely, Gregory; Detterbeck, Frank; Simone, Charles B; Ahmad, Usman; Huang, James; Korst, Robert; Rajan, Arun; Rimner, Andreas

    2017-04-01

    Thymic carcinomas are rare epithelial malignancies with limited data to guide management. To identify areas of agreement and variability in current clinical practice, a 16-question electronic survey was given to members of the International Thymic Malignancy Interest Group (ITMIG). Areas of controversy were discussed with the Thymic Carcinoma Working Group and consensus was achieved, as described. A total of 100 ITMIG members responded. There was general agreement regarding the role for multimodality therapy with definitive surgical resection in physically fit patients with advanced but resectable disease. Areas of controversy included the need for histologic confirmation before surgery, the role of adjuvant therapy, the optimal first-line chemotherapy regimen, and the recommended treatment course for marginally resectable disease with invasion into the great vessels, pericardium, and lungs. The results of the questionnaire provide a description of the management of thymic carcinoma by 100 ITMIG members with a specific interest or expertise in thymic malignancies. Although there was agreement in some areas, clinical practice appears to vary significantly. There is a great need for collaborative research to identify optimal evaluation and treatment strategies. Given the need for multimodality therapy in many cases, a multidisciplinary discussion of the management of patients with thymic carcinoma is critical. Copyright © 2016 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

  8. The effect of age on thymic function

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    Donald B. Palmer

    2013-10-01

    Full Text Available Age-related regression of the thymus is associated with a decline in naïve T cell output. This is thought to contribute to the reduction in T cell diversity seen in older individuals and linked with increased susceptibility to infection, autoimmune disease and cancer. Thymic involution is one of the most dramatic and ubiquitous changes seen in the ageing immune system, but the mechanisms which underlying this process are poorly understood. However, a picture is emerging, implicating the involvement of both extrinsic and intrinsic factors. In this review we assess the role of the thymic microenvironment as a potential target that regulates thymic involution, question whether thymocyte development in the aged thymus is functionally impaired and explore the kinetics of thymic involution.

  9. Minimally Invasive Surgery in Thymic Malignances

    Directory of Open Access Journals (Sweden)

    Wentao FANG

    2018-04-01

    Full Text Available Surgery is the most important therapy for thymic malignances. The last decade has seen increasing adoption of minimally invasive surgery (MIS for thymectomy. MIS for early stage thymoma patients has been shown to yield similar oncological results while being helpful in minimize surgical trauma, improving postoperative recovery, and reduce incisional pain. Meanwhile, With the advance in surgical techniques, the patients with locally advanced thymic tumors, preoperative induction therapies or recurrent diseases, may also benefit from MIS in selected cases.

  10. Images in pediatrics: the thymic sail sign and thymic wave sign.

    Science.gov (United States)

    Alves, Nuno D; Sousa, Marta

    2013-01-01

    The authors present a radiographic image portraying the "thymic sail sign" and the "thymic wave sign," both normal findings in infant radiographs and present a short description of these signs. These are distinguished from pathologic findings such as the "spinnaker-sail sign" in pneumomediastinum.

  11. Direct analysis of thymic function in children with Down's syndrome

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    Meschiari Liviana

    2005-02-01

    Full Text Available Abstract Background Down's syndrome (DS is characterized by several immunological defects, especially regarding T cell compartment. DS is considered the best example of accelerated ageing in humans. Direct observations of the thymus have shown that in DS this organ undergoes severe histological and morphological changes. However, no data on its capacity to generate T cells are present in the literature. Here, using a new technology based upon real time PCR, we have investigated the capacity of the thymus to produce and release newly generated T lymphocytes (the so called "recent thymic emigrants", RTE in children with DS. Methods We studied 8 children affected by DS, aged 2–7 years, compared with 8 age- and sex-matched healthy controls. Flow cytometry was used to determine different lymphocytes subsets. Real time PCR with the Taqman system was used to quantify the amount of RTE, i.e. peripheral blood lymphocytes that express the T cell receptor rearrangement excision circles (TREC. Results In comparison with control children, those with DS had a significant lower number of TREC+ peripheral blood cells. Moreover, in DS children but not in controls, a strong negative correlation between age and the levels of TREC+ cells was found. Conclusions The direct measure of thymic output indicates that the impairment of the organ results in a reduced production of newly generated T cells. This observation could suggest that cytokines able to modulate thymic function, such as interleukins, could be useful to improve the functionality of the organ and to treat the immunodeficiency present in DS subjects.

  12. Frequent silencing of RASSF1A by DNA methylation in thymic neuroendocrine tumours.

    Science.gov (United States)

    Kajiura, Koichiro; Takizawa, Hiromitsu; Morimoto, Yuki; Masuda, Kiyoshi; Tsuboi, Mitsuhiro; Kishibuchi, Reina; Wusiman, Nuliamina; Sawada, Toru; Kawakita, Naoya; Toba, Hiroaki; Yoshida, Mitsuteru; Kawakami, Yukikiyo; Naruto, Takuya; Imoto, Issei; Tangoku, Akira; Kondo, Kazuya

    2017-09-01

    Aberrant methylation of promoter CpG islands (CGIs) of tumour suppressor genes is a common epigenetic mechanism underlying cancer pathogenesis. The methylation patterns of thymic tumours have not been studied in detail since such tumours are rare. Herein, we sought to identify genes that could serve as epigenetic targets for thymic neuroendocrine tumour (NET) therapy. Genome-wide screening for aberrantly methylated CGIs was performed in three NET samples, seven thymic carcinoma (TC) samples, and eight type-B3 thymoma samples. The methylation status of thymic epithelial tumours (TETs) samples was validated by pyrosequencing in a larger cohort. The expression status was analysed by quantitative polymerase chain reaction (PCR) and immunohistochemistry. We identified a CGI on a novel gene, RASSF1A, which was strongly hypermethylated in NET, but not in thymic carcinoma or B3 thymoma. RASSF1A was identified as a candidate gene statistically and bibliographically, as it showed frequent CGI hypermethylation in NET by genome-wide screening. Pyrosequencing confirmed significant hypermethylation of a RASSF1A CGI in NET. Low-grade NET tissue was more strongly methylated than high-grade NET. Quantitative PCR and immunohistochemical staining revealed that RASSF1A mRNA and protein expression levels were negatively regulated by DNA methylation. RASSF1A is a tumour suppressor gene epigenetically dysregulated in NET. Aberrant methylation of RASSF1A has been reported in various tumours, but this is the first report of RASSF1A hypermethylation in TETs. RASSF1A may represent an epigenetic therapeutic target in thymic NET. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Thymic hyperplasia - clinical course and imaging diagnostic

    International Nuclear Information System (INIS)

    Drebov, R.; Panov, M.; Totev, M.; Deliverski, T.; Tcandev, I.; Velkovski, I.

    2006-01-01

    The real thymic hyperplasia is benign disease sometimes simulating malignant tumours. The aim of this study is to analyse the clinical symptoms of real thymic hyperplasia and the results from imaging diagnostic based on our clinical material. Clinical material include 27 children, aged from two months to 15 years, admitted in department of thoracic surgery, for a period of 20 years (1985 - 2004). We retrospectively analyze the clinical signs and results from X-ray investigation, CT (Siemens Somatom DRG and Philips Secura) and echocardiography (Acuson TX, 5 and 7 MHz). We discuss the diagnostic value of different methods as well as typical and atypical findings. (authors)

  14. Computed tomography of thymic abnormalities: review of 10 patients

    International Nuclear Information System (INIS)

    Marins, J.L.C.; Brito Pacheco, E.M. de; Cazerta, N.M.G.; Silva, M.J.G. da

    1990-01-01

    Chest radiographs and computed tomographic scans of the mediastinum were correlated with pathologic findings of the thymus following thymectomy in 10 patients with thymic disease. There were five patients with thymoma, four with thymic hiperplasia and one with benign thymic cyst. Computed tomography shoud be the imaging method of choice following plain chest radiographs when a suspect thymic abnormality requires further evaluation. Recognition of variations in the normal location, size, shape and density of the thymus prevents misinterpretation as abnormal mediastinal mass. Furthermore, knowledge of the normal computed tomography appearance has proved helpful in evaluating thymic abnormalities. (author)

  15. Thymic enlargement in patients with hyperthyroidism

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    Myung, Jae Sung; Goo, Jin Mo; Im, Jung Gi [College of medicine and the Institute of Radiation Medicine, Seoul National University, Seoul (Korea, Republic of); Kim, Mi Young [Sejong General Hospital, Seoul (Korea, Republic of); Park, Yang Hee [National Police Hospital, Seoul (Korea, Republic of)

    2000-08-01

    To evaluate the radiologic findings and clinical feasibility of thymic enlargement in patients with hyperthyroidism. Seven patients with hyperthyroidism and anterior mediastinal bulging revealed by chest radiography were evaluated. The CT findings were analyzed with regard to the shape of the anterior mediastinal mass, surrounding infiltration, and enlargement of mediastinal lymph nodes. Whether or not tumor markers (alpha-fetoprotein, beta-human chorionic gonadotrophin, and chorionic embryonic antigen) showed increased levels was determined, and the size and thickness of the anterior mediastinal mass were measured and compared with previously described age-matched thymus data. In addition, changes in the thyroid gland were evaluated. In all seven patients, anterior mediastinal masses were bi-lobed, with no surrounding infiltration or enlarged mediastinal lymph node, and tumor marker levels showed no increase. The masses were therefore considered to be thymus. In six patients, the size of the thymus exceeded two upper standard deviations of mean value and in one patient, it was smaller than this. In three patients, PCNB (percutaneous needle biopsy) revealed normal thymic tissue and in two, follow-up chest PA demonstrated no interval change. CT showed that in three patients, the thyroid glands were diffusely enlarged. In patients with hyperthyroidism, an anterior mediastinal mass seen on chest radiographs was due to thymic enlargement. The recognition of CT findings of thymic enlargement in such patients may avoid unnecessary biopsy. (author)

  16. PICTORIAL ESSAY Thymic masses: A radiological review

    African Journals Online (AJOL)

    On chest X-ray, thymic abnormalities typically manifest as focal or diffuse ... Department of Radiodiagnosis and Imaging, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi, India. Corresponding author: B ... are considered of primary mediastinal origin if there is neither a detectable gonadal primary nor.

  17. Dietary modulation of thymic enzymes.

    Science.gov (United States)

    Susana, Feliu María; Paula, Perris; Slobodianik, Nora

    2014-01-01

    Malnutrition is a complex syndrome caused by an inadequate intake of energy, protein, minerals and vitamins which affects the immune system. Nutritional imbalances, present in children with energy-protein malnutrition and infections, make defining the specific effects of each of them on the thymus difficult. For this reason, it is necessary to design an experimental model in animals that could define a single variable. As the thymus atrophy described in humans is similar to that observed in murines, a rat experimental model makes the extrapolation to man possible. Some authors suggest that the activity of Adenosine Deaminase (ADA) and Purine Nucleoside Phosphorylase (PNP)--involved in purine metabolism--have an influence on T lymphocyte development and the immune system, due to intracellular accumulation of toxic levels of deoxynucleotides. Studies in our group, performed in an experimental model on Wistar growing rats, have demonstrated that protein deficiency or imbalance in the profile of essential amino acids in the diet, produce loss of thymus weight, reduction in the number of thymocytes, a diminished proportion of T cells presenting the W3/13 antigenic determinant and DNA content with concomitant increase in cell size, and the proportion of immature T cells and activity of ADA and PNP, without modifying the activity of 5´Nucleotidase in the thymus. It is important to point out that there were neither differences in energy intake between experimental groups and their controls, nor clinical symptoms of deficiency of other nutrients. The increase in these thymic enzyme activities was an alternative mechanism to avoid the accumulation of high levels of deoxynucleotides, which would be toxic for T lymphocytes. On the other hand, the administration of a recovery diet, with a high amount of high quality protein, was able to reverse the mentioned effects. The quick reply of Adenosine Deaminase to nutritional disorders and the following nutritional recovery, points

  18. The International Thymic Malignancy Interest Group thymic initiative: a state-of-the-art study of thymic malignancies.

    Science.gov (United States)

    Detterbeck, Frank; Korst, Robert

    2014-01-01

    Thymic malignancies are relatively rare tumors. A general lack of knowledge, misconceptions about benignancy, confusion about the definition of terms, and variability in reporting of outcomes have further hampered progress in these diseases. The International Thymic Malignancy Interest Group has emerged to counter these challenges and has brought together a worldwide multidisciplinary community determined to improve outcomes for these patients. Although the organization is young (initiated in 2010), major early accomplishments have created a foundation and infrastructure for scientific research. These include consensus definitions of terms, an unprecedented global database, development of practical clinical resources and, together with the International Association for the Study of Lung Cancer, development of proposals for the first formal stage classification of these malignant tumors. Many articles have been published or are under way, and a second phase of projects building on the early success is proceeding. The greatest accomplishment of the International Thymic Malignancy Interest Group lies in the establishment of an open culture of collaboration and the engagement of a broad group of individuals united by a common mission. It is a testament to what can be achieved, despite ongoing and inherent challenges, by determination and a collective effort. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Imaging of thymus in myasthenia gravis: From thymic hyperplasia to thymic tumor

    International Nuclear Information System (INIS)

    Priola, A.M.; Priola, S.M.

    2014-01-01

    Myasthenia gravis (MG) is an autoimmune disorder often associated with thymic abnormalities. At onset, thymic lymphoid hyperplasia (TLH) and thymoma can be found in up to 65% and 15% of patients, respectively. Diagnostic imaging is crucial in this setting in order to detect the presence and type of the thymic abnormality and in the preoperative planning, when indicated. Chest radiography has a minor role due to its low accuracy. Computed tomography is the imaging modality of choice, although the differentiation between a small thymoma and TLH that appears as a focal soft-tissue mass may be not possible. Magnetic resonance imaging (MRI) is not usually employed, but it is useful in equivocal cases, especially in differentiating focal TLH from thymoma by using chemical-shift sequences for defining the proper management. In addition, diffusion-weighted (DW)-MRI can differentiate lipid-poor normal/hyperplastic thymus from thymoma and could be useful in differentiating non-advanced from advanced thymomas. Positron emission tomography (PET)-CT is not helpful in distinguishing early from advanced thymoma but can be used to differentiate thymic carcinoma from thymoma. Hereby, we discuss the imaging features of thymic abnormalities in MG, even focusing on novel aspects of chemical-shift and DW-MRI

  20. Radiation carcinogenesis in mouse thymic lymphomas

    International Nuclear Information System (INIS)

    Kominami, Ryo; Niwa, Ohtsura

    2006-01-01

    Ionizing radiation is a well-known carcinogen for various human tissues and a complete carcinogen that is able to initiate and promote neoplastic progression. Studies of radiation-induced mouse thymic lymphomas, one of the classic models in radiation carcinogenesis, demonstrated that even the unirradiated thymus is capable of developing into full malignancy when transplanted into the kidney capsule or subcutaneous tissue of irradiated mice. This suggests that radiation targets tissues other than thymocytes to allow expansion of cells with tumorigenic potential in the thymus. The idea is regarded as the ''indirect mechanism'' for tumor development. This paper reviews the indirect mechanism and genes affecting the development of thymic lymphomas that we have analyzed. One is the Bcl11b/Rit1 tumor suppressor gene and the other is Mtf-1 gene affecting tumor susceptibility. (author)

  1. Thymic irradiation and chronic myelogenous leukemia

    International Nuclear Information System (INIS)

    Shimaoka, K.; Sokal, J.E.

    1977-01-01

    Two cases of Ph positive chronic myelogenous leukemia with a history of thymic irradiation are presented. Both patients received radiation therapy from low voltage x-ray equipment at two to three months of age. Leukemia developed 18 and 22 years later. Presentation, response to antileukemic therapy, and clinical course did not differ from that of other patients with this disease treated in our department

  2. Thymic pathology and cardiac myxomas: Coincidence or a closer relationship?

    Science.gov (United States)

    Moraitis, Sotirios D; Agrafiotis, Apostolos C; Pappas, Dimitrios; Pothitakis, Chrysovalantis; Stergianni, Maria; Koukis, Ioannis

    2018-04-30

    Myxomas are the most common benign cardiac tumors and are located more frequently in the left atrium. In the literature there are cases describing the coexistence of thymic tumors and cardiac myxomas. In the case reported herein, during the resection of a cardiac myxoma, an enlarged thymus gland was encountered and resected. The histological exam revealed a thymic hyperplasia. The aim of this case study is to assess the need of conducting further studies in order to identify a common histological pathway between thymic lesions and cardiac myxomas. The diagnosis of a cardiac myxoma could justify a further workup of the anterior mediastinum in order not to overlook a lesion of thymic origin.

  3. Exploring the link between innate immune activation and thymic function by measuring sCD14 and TRECs in HIV patients living in Belgium.

    Directory of Open Access Journals (Sweden)

    Adrien De Voeght

    Full Text Available Microbial translocation is now viewed as a central event in the pathogenesis of chronic inflammation during HIV infection. Thymic function failure is another crucial factor involved in HIV disease progression. The goal of this study was to explore the hypothesis of potential links between microbial translocation and thymic function in HIV-1 patients living in Belgium. The extent of microbial translocation was assessed through the measurement of soluble CD14 (sCD14. T-cell receptor excision circles (sjTRECs and dβTRECs were used as a measure of thymic function. Data were collected from 75 HIV-infected patients. Simple and complex linear regressions were done to analyze the link between these two processes. We found a statistically relevant negative correlation between thymopoiesis (sjTREC and sCD14 level (p = 0.004. These results suggest a link between thymic function failure, microbial translocation and innate immune activation.

  4. HLA-B*39:06 Efficiently Mediates Type 1 Diabetes in a Mouse Model Incorporating Reduced Thymic Insulin Expression.

    Science.gov (United States)

    Schloss, Jennifer; Ali, Riyasat; Racine, Jeremy J; Chapman, Harold D; Serreze, David V; DiLorenzo, Teresa P

    2018-04-09

    Type 1 diabetes (T1D) is characterized by T cell-mediated destruction of the insulin-producing β cells of the pancreatic islets. Among the loci associated with T1D risk, those most predisposing are found in the MHC region. HLA-B*39:06 is the most predisposing class I MHC allele and is associated with an early age of onset. To establish an NOD mouse model for the study of HLA-B*39:06, we expressed it in the absence of murine class I MHC. HLA-B*39:06 was able to mediate the development of CD8 T cells, support lymphocytic infiltration of the islets, and confer T1D susceptibility. Because reduced thymic insulin expression is associated with impaired immunological tolerance to insulin and increased T1D risk in patients, we incorporated this in our model as well, finding that HLA-B*39:06-transgenic NOD mice with reduced thymic insulin expression have an earlier age of disease onset and a higher overall prevalence as compared with littermates with typical thymic insulin expression. This was despite virtually indistinguishable blood insulin levels, T cell subset percentages, and TCR Vβ family usage, confirming that reduced thymic insulin expression does not impact T cell development on a global scale. Rather, it will facilitate the thymic escape of insulin-reactive HLA-B*39:06-restricted T cells, which participate in β cell destruction. We also found that in mice expressing either HLA-B*39:06 or HLA-A*02:01 in the absence of murine class I MHC, HLA transgene identity alters TCR Vβ usage by CD8 T cells, demonstrating that some TCR Vβ families have a preference for particular class I MHC alleles. Copyright © 2018 by The American Association of Immunologists, Inc.

  5. CT differentiation of invasive thymoma and thymic carcinoma

    International Nuclear Information System (INIS)

    Lee, Eun Jung; Jung, Gyoo Sik; Kim, Seong Min; Huh, Jin Do; Joh, Young Duk; Shin, Mi Jung; Kim, Jung Sik; Suh, Soo Jhi

    1998-01-01

    In order to determine the differential points between them, we analyzed the CT findings of invasive thymoma and thymic carcinoma. We retrospectively reviewed the CT scans of 14 patients with invasive thymoma and 15 with thymic carcinoma, confirmed by surgery(n=3D19) or percutaneous needle aspiration(n=3D10) between 1988 and 1996. CT findings were evaluated in each group for intrathoracic spread(posterior, direct posterior, and anterolateral), obliteration of the fat plane between the mass and vascular structures, vessel encasement, invasion of adjacent mediastinal structures, pleural implants, mediastinal nodes and distant metastasis. Direct posterior spread was more common in thymic carcinoma than invasive thymoma;it was seen in one case (7%) of invasive thymoma and 12(80%) of thymic carcinoma(p=3D0.00). Posterior spread was seen in six cases (43%) of in vasive thymoma and nine (60%) of thymic carcinoma. Anterolateral spread was seen only in two cases (13%) of thymic carcinoma. Obliteration of the fat plane was seen in nine cases (64%) of invasive thymoma and 14 (93%) of thymic carcinoma, while vessel encasement was seen in two cases (14%) of invasive thymoma and 13(87%) of thymic carcinoma(p=3D0.00). Invasion of adjacent structures was seen in two cases (14%) of invasive thymoma and eight (53%) of thymic carcinoma. Pleural implants were more common in invasive thymoma than thymic carcinoma, being seen in six cases (43%) of the former and one (7%) of the latter(p=3D0.04). Mediastinal lymphadenopathy was seen in three cases (21%) of invasive thymoma and ten (67%) of thymic carcinoma. Distant metastases were observed only in six cases (40%) of thymic carcinoma(p=3D0.02). Although differentiation between invasive thymoma and thymic carcinoma is difficult on the basis of CT findings, there are certain differential points. Thymic carcinomas showed a higher rate of direct posterior intrathoracic spread, vessel encasement, mediastinal nodes and distant metastases than

  6. Immune activation is associated with decreased thymic function in ...

    African Journals Online (AJOL)

    Background: Reduced thymic function causes poor immunological reconstitution in human immunodeficiency virus (HIV)-positive patients on combined antiretroviral therapy (cART). The association between immune activation and thymic function in asymptomatic HIVpositive treatment-naive individuals has thus far not been ...

  7. Massive thymic hemorrhage and hemothorax occurring in utero.

    Science.gov (United States)

    Gargano, Giancarlo; Paltrinieri, Anna Lucia; Gallo, Claudio; Di Pancrazio, Luciana; Roversi, Maria Federica; Ferrari, Fabrizio

    2015-11-14

    Thymic enlargement is a common and physiological finding in children and neonates' X-rays, but it is usually asymptomatic. Occasionally it can cause respiratory distress. In most cases the aetiology of this expansion remains unclear and it is diagnosed as a thymic hyperplasia. True thymic hyperplasia is defined as a gland expansion, both in size and weight, while maintaining normal microscopic architecture. Often it is a diagnosis of exclusion and prognosis is good. Thymic haemorrhage is an unusual condition related to high foetal and neonatal mortality. We report a case of spontaneous massive thymic haemorrhage in a newborn developing at birth acute respiratory distress associated with severe bilateral haemothorax. Thymic enlargement was evident after pleural evacuation and confirmed by radiographic, Computed Tomography (CT) images and Magnetic Resonance Imaging (MRI) sequences. The spontaneous resolution of this enlargement seen with CT scan and MRI sequences suggested a thymic haemorrhage; surgery was not necessary. Thymic haemorrhage should be considered in newborn infants with pleural effusion, mediastinal space enlargement and Respiratory Distress.

  8. Intrathymic radioresistant stem cells follow an IL-2/IL-2R pathway during thymic regeneration after sublethal irradiation

    International Nuclear Information System (INIS)

    Zuniga-Pfluecker, J.C.K.; Kruisbeek, A.M.

    1990-01-01

    Sublethally irradiated mice undergo thymic regeneration which follows a phenotypic pattern of events similar to that observed during normal fetal development. Thymic regeneration after irradiation is the product of a limited pool of intrathymic radioresistant stem cells undergoing simultaneous differentiation. We show that in this model of T cell development, thymic regeneration follows a pathway in which the IL-2R is transiently expressed on CD4-/CD8- cells. IL-2R expression occurred during the exponential growth period of thymic regeneration, and IL-2R blocking prevented this explosive growth. Flow cytometry analysis revealed that the IL-2R blockade affected primarily the development of the immature CD3-/CD4-/CD8- (triple negative) cells and their ability to generate CD3+/CD4+/CD8+ or CD3+/CD4+/CD8- and CD3+/CD4-/CD8+ thymocytes. Thus, our findings demonstrate that blocking of the IL-2R resulted in an arrest in proliferation and differentiation by intrathymic radioresistant stem cells, indicating that the IL-2/IL-2R pathway is necessary for the expansion of immature triple negative T cells

  9. Increased cFLIP expression in thymic epithelial tumors blocks autophagy via NF-κB signalling.

    Science.gov (United States)

    Belharazem, Djeda; Grass, Albert; Paul, Cornelia; Vitacolonna, Mario; Schalke, Berthold; Rieker, Ralf J; Körner, Daniel; Jungebluth, Philipp; Simon-Keller, Katja; Hohenberger, Peter; Roessner, Eric M; Wiebe, Karsten; Gräter, Thomas; Kyriss, Thomas; Ott, German; Geserick, Peter; Leverkus, Martin; Ströbel, Philipp; Marx, Alexander

    2017-10-27

    The anti-apoptotic cellular FLICE-like inhibitory protein cFLIP plays a pivotal role in normal tissues homoeostasis and the development of many tumors, but its role in normal thymus (NT), thymomas and thymic carcinomas (TC) is largely unknown. Expression, regulation and function of cFLIP were analyzed in biopsies of NT, thymomas, thymic squamous cell carcinomas (TSCC), thymic epithelial cells (TECs) derived thereof and in the TC line 1889c by qRT-PCR, western blot, shRNA techniques, and functional assays addressing survival, senescence and autophagy. More than 90% of thymomas and TSCCs showed increased cFLIP expression compared to NT. cFLIP expression declined with age in NTs but not in thymomas. During short term culture cFLIP expression levels declined significantly slower in neoplastic than non-neoplastic primary TECs. Down-regulation of cFLIP by shRNA or NF-κB inhibition accelerated senescence and induced autophagy and cell death in neoplastic TECs. The results suggest a role of cFLIP in the involution of normal thymus and the development of thymomas and TSCC. Since increased expression of cFLIP is a known tumor escape mechanism, it may serve as tissue-based biomarker in future clinical trials, including immune checkpoint inhibitor trials in the commonly PD-L1 high thymomas and TCs.

  10. Rag defects and thymic stroma: lessons from animal models

    Directory of Open Access Journals (Sweden)

    Veronica eMarrella

    2014-06-01

    Full Text Available Thymocytes and thymic epithelial cells (TECs cross-talk is essential to support T-cell development and preserve thymic architecture and maturation of TECs and Foxp3+ natural regulatory T (nTreg cells. Accordingly, disruption of thymic lymphostromal cross-talk may have major implications on the thymic mechanisms that govern T cell tolerance. Several genetic defects have been described in humans that affect early stages of T cell development (leading to Severe Combined Immune Deficiency, SCID or late stages in thymocyte maturation (resulting in combined immunodeficiency. Hypomorphic mutations in SCID-causing genes may allow for generation of a limited pool of T lymphocytes with a restricted repertoire. These conditions are often associated with infiltration of peripheral tissues by activated T cells and immune dysregulation, as best exemplified by Omenn syndrome (OS. In this review, we will discuss our recent findings on abnormalities of thymic microenvironment in OS with a special focus of defective maturation of TECs, altered distribution of thymic dendritic cells (DCs and impairment of deletional and non-deletional mechanisms of central tolerance. Here, taking advantage of mouse models of OS and atypical SCID, we will discuss how modifications in stromal compartment impact and shape lymphocyte differentiation, and vice versa how inefficient T cell signalling results in defective stromal maturation. These findings are instrumental to understand the extent to which novel therapeutic strategies should act on thymic stroma to achieve full immune reconstitution.

  11. Titan's hydrodynamically escaping atmosphere

    Science.gov (United States)

    Strobel, Darrell F.

    2008-02-01

    The upper atmosphere of Titan is currently losing mass at a rate ˜(4-5)×10 amus, by hydrodynamic escape as a high density, slow outward expansion driven principally by solar UV heating by CH 4 absorption. The hydrodynamic mass loss is essentially CH 4 and H 2 escape. Their combined escape rates are restricted by power limitations from attaining their limiting rates (and limiting fluxes). Hence they must exhibit gravitational diffusive separation in the upper atmosphere with increasing mixing ratios to eventually become major constituents in the exosphere. A theoretical model with solar EUV heating by N 2 absorption balanced by HCN rotational line cooling in the upper thermosphere yields densities and temperatures consistent with the Huygens Atmospheric Science Investigation (HASI) data [Fulchignoni, M., and 42 colleagues, 2005. Nature 438, 785-791], with a peak temperature of ˜185-190 K between 3500-3550 km. This model implies hydrodynamic escape rates of ˜2×10 CHs and 5×10 Hs, or some other combination with a higher H 2 escape flux, much closer to its limiting value, at the expense of a slightly lower CH 4 escape rate. Nonthermal escape processes are not required to account for the loss rates of CH 4 and H 2, inferred by the Cassini Ion Neutral Mass Spectrometer (INMS) measurements [Yelle, R.V., Borggren, N., de la Haye, V., Kasprzak, W.T., Niemann, H.B., Müller-Wodarg, I., Waite Jr., J.H., 2006. Icarus 182, 567-576].

  12. Isolated splenic metastasis from a thymic carcinoma: A case report.

    Science.gov (United States)

    Chen, Dongmei; Meng, Xiangying; Zhao, Yaowei; Wu, Shikai

    2016-09-01

    Thymic carcinomas are rare tumors that arise in the anterior mediastinum. Most of these malignancies develop local metastases limited in the thorax. Splenic metastases from thymic carcinomas are extremely rare. Here we report a case of isolated splenic metastasis from a 38-year-old female patient with Stage IV thymic carcinoma, who was treated with chemoradiotherapy. At twenty-2 months follow-up, the patient was found to have an isolated spleen metastasis, which was treated by Cyberknife with a reduced size of the metastasis, representing a partial response. Although splenic metastasis is a rare phenomenon, physicians need to be aware of the possibility of such metastases.

  13. Thymic nurse cells and thymic repopulation after whole body sublethal irradiation in mice

    International Nuclear Information System (INIS)

    Houben-Defresne, M.P.; Varlet, A.; Boniver, J.

    1984-01-01

    Thymic Nurse Cells (TNCs) are lymphoepithelial complexes which are thought to play a role in the early stages of the intrathymic differentiation pathway. Their repopulation kinetics were analyzed in mice after sublethal whole-body irradiation. Changes of the number of TNCs per thymus were parallel with the evolution of the whole thymocyte population. Particularly, a first wave of TNCs restoration was followed by a secondary depletion and a final recovery. This suggests that TNCs restoration is related to the proliferating progeny of intrathymic radioresistant thymocytes. When normal bone marrow cells were grafted intravenously after irradiation, no secondary depletion was found. This pattern of restoration was obviously related to thymic repopulation by cells which were derived from the inoculated bone marrow. Homing studies with FITC labelled bone marrow cells showed that inoculated bone marrow cells did not penetrate TNCs early after irradiation. Later on, when immigrant cells started to proliferate, they were found preferentially within TNCs before spreading in the whole thymus. (Auth.)

  14. Three distinct subsets of thymic epithelial cells in rats and mice defined by novel antibodies.

    Directory of Open Access Journals (Sweden)

    Yasushi Sawanobori

    Full Text Available Thymic epithelial cells (TECs are thought to play an essential role in T cell development and have been detected mainly in mice using lectin binding and antibodies to keratins. Our aim in the present study was to create a precise map of rat TECs using antibodies to putative markers and novel monoclonal antibodies (i.e., ED 18/19/21 and anti-CD205 antibodies and compare it with a map from mouse counterparts and that of rat thymic dendritic cells.Rat TECs were subdivided on the basis of phenotype into three subsets; ED18+ED19+/-keratin 5 (K5+K8+CD205+ class II MHC (MHCII+ cortical TECs (cTECs, ED18+ED21-K5-K8+Ulex europaeus lectin 1 (UEA-1+CD205- medullary TECs (mTEC1s, and ED18+ED21+K5+K8dullUEA-1-CD205- medullary TECs (mTEC2s. Thymic nurse cells were defined in cytosmears as an ED18+ED19+/-K5+K8+ subset of cTECs. mTEC1s preferentially expressed MHCII, claudin-3, claudin-4, and autoimmune regulator (AIRE. Use of ED18 and ED21 antibodies revealed three subsets of TECs in mice as well. We also detected two distinct TEC-free areas in the subcapsular cortex and in the medulla. Rat dendritic cells in the cortex were MHCII+CD103+ but negative for TEC markers, including CD205. Those in the medulla were MHCII+CD103+ and CD205+ cells were found only in the TEC-free area.Both rats and mice have three TEC subsets with similar phenotypes that can be identified using known markers and new monoclonal antibodies. These findings will facilitate further analysis of TEC subsets and DCs and help to define their roles in thymic selection and in pathological states such as autoimmune disorders.

  15. The Wnt Signaling Antagonist Kremen1 is Required for Development of Thymic Architecture

    Directory of Open Access Journals (Sweden)

    Masako Osada

    2006-01-01

    Full Text Available Wnt signaling has been reported to regulate thymocyte proliferation and selection at several stages during T cell ontogeny, as well as the expression of FoxN1 in thymic epithelial cells (TECs. Kremen1 (Krm1 is a negative regulator of the canonical Wnt signaling pathway, and functions together with the secreted Wnt inhibitor Dickkopf (Dkk by competing for the lipoprotein receptor-related protein (LRP-6 co-receptor for Wnts. Here krm1 knockout mice were used to examine krm1 expression in the thymus and its function in thymocyte and TEC development. krm1 expression was detected in both cortical and medullary TEC subsets, as well as in immature thymocyte subsets, beginning at the CD25+CD44+ (DN2 stage and continuing until the CD4+CD8+(DP stage. Neonatal mice show elevated expression of krm1 in all TEC subsets. krm1− / − mice exhibit a severe defect in thymic cortical architecture, including large epithelial free regions. Much of the epithelial component remains at an immature Keratin 5+ (K5 Keratin 8+(K8 stage, with a loss of defined cortical and medullary regions. A TOPFlash assay revealed a 2-fold increase in canonical Wnt signaling in TEC lines derived from krm1− / − mice, when compared with krm1+ / + derived TEC lines. Fluorescence activated cell sorting (FACS analysis of dissociated thymus revealed a reduced frequency of both cortical (BP1+EpCAM+ and medullary (UEA-1+ EpCAMhi epithelial subsets, within the krm1− / − thymus. Surprisingly, no change in thymus size, total thymocyte number or the frequency of thymocyte subsets was detected in krm1− / − mice. However, our data suggest that a loss of Krm1 leads to a severe defect in thymic architecture. Taken together, this study revealed a new role for Krm1 in proper development of thymic epithelium.

  16. Effect of granulocyte colony-stimulating factor on murine thymic emigration and subsets reconstitution after a sublethal dose of irradiation

    International Nuclear Information System (INIS)

    Zhao Hongxia; Guo Mei; Sun Xuedong; Ai Huisheng

    2011-01-01

    Objective: To investigate the effects of recombinant human granulocyte colony stimulating factor (G-CSF) on murine thymic emigration and subsets reconstitution after a sublethal dose of irradiation. Methods: Female BALB/c mice were irradiated with a 6.0 Gy of γ-ray total-body irradiation and then randomly divided into GCSF group and control group. For mice in the GCSF group, recombinant human G-CSF 100 μg · kg -1 · d -1 was injected subcutaneously once daily for 14 continuous days and mice in the control group were given the same volume of phosphate buffered solution (PBS). At 7, 14, 21 and 28 days later, mice were killed and thymus mononuclear cell suspension were analyzed by flow cytometry for the percentage of the four stages of thymic CD4 - CD8 - double negative cells (DN1-4) and the CD4 + CD8 + double positive ( CD4 + CD8 + DP), CD4 + CD8 - single positive (CD4 + SP), CD4 - CD8 + single positive cells (CD8 + SP).Real-time PCR was used for detection and quantitation of murine T cell receptor rearrangement excision circles (sjTRECs) of the thymic cells of 30 and 60 d after irradiation. Results: The percentage of thymic DN1 cells in GCSF group was significantly higher than that of the control group 7 d after irradiation (t=9.59, P<0.05). 21 d later, the proportion of thymic DN3 and DN4 cells were higher than those of the control group (t=16.37, 7.6, P<0.05). The percentage of thymic CD4 + CD8 + DP cells decreased 7 d after irradiation,increased at 14 d, decreased again at 21 days,and then got a permanent recover. The percentage of thymic CD4 + CD8 + DP cells in the GCSF group recovered to normal and was significantly higher than that of the control group 28 days after irradiation (t=12.22, P<0.05). The percentage of thymic CD8 + SP cells of the GCSF group was significantly higher than that of the control group 21 d after irradiation (t=3.77, P<0.05), while G-CSF had no obvious influence on the percentage of the thymic CD4 + SP cells. The sjTRECs copies in the

  17. Thymic masses: A radiological review | Mittal | SA Journal of Radiology

    African Journals Online (AJOL)

    Abstract. Various thymic masses and their normal variations have different pathological and management consequences. Radiologists and clinicians should be aware of these entities so that appropriate and timely treatment can be given.

  18. Administration of RANKL boosts thymic regeneration upon bone marrow transplantation.

    Science.gov (United States)

    Lopes, Noella; Vachon, Hortense; Marie, Julien; Irla, Magali

    2017-06-01

    Cytoablative treatments lead to severe damages on thymic epithelial cells (TECs), which result in delayed de novo thymopoiesis and a prolonged period of T-cell immunodeficiency. Understanding the mechanisms that govern thymic regeneration is of paramount interest for the recovery of a functional immune system notably after bone marrow transplantation (BMT). Here, we show that RANK ligand (RANKL) is upregulated in CD4 + thymocytes and lymphoid tissue inducer (LTi) cells during the early phase of thymic regeneration. Importantly, whereas RANKL neutralization alters TEC recovery after irradiation, ex vivo RANKL administration during BMT boosts the regeneration of TEC subsets including thymic epithelial progenitor-enriched cells, thymus homing of lymphoid progenitors, and de novo thymopoiesis. RANKL increases specifically in LTi cells, lymphotoxin α, which is critical for thymic regeneration. RANKL treatment, dependent on lymphotoxin α, is beneficial upon BMT in young and aged individuals. This study thus indicates that RANKL may be clinically useful to improve T-cell function recovery after BMT by controlling multiple facets of thymic regeneration. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

  19. Restricting wolves risks escape

    Science.gov (United States)

    Mech, L. David; Ballard, Warren; Bangs, Ed; Ream, Bob

    2010-01-01

    Implementing the proposal set forth by Licht and colleagues (BioScience 60: 147–153) requires restricting wolves to tiny "islands," areas that are magnitudes smaller than the ranges of most wolf populations. Wolves naturally have large ranges; restricting their spatial needs increases the risk of wolves escaping, exacerbating public relations and political and legal problems.

  20. Thymic epithelial tumours: from basic principles to individualised treatment strategies

    Directory of Open Access Journals (Sweden)

    Nicolas Girard

    2013-03-01

    Full Text Available Thymic epithelial tumours represent a wide range of anatomical, clinical, histological and molecular malignant entities that may be aggressive and difficult to treat. The histopathological classification distinguishes thymomas from thymic carcinomas. Thymomas may be associated with autoimmune disorders. The management of thymic epithelial tumours is a paradigm of co-operation between clinicians, surgeons and pathologists, from establishing the diagnosis to organising the multimodal therapeutic strategy. Surgery is the mainstay of the curative-intent treatment, as complete resection represents the most significantly favourable prognostic factor on overall survival. In case of invasion of intra-thoracic structures and/or dissemination to the pleura and the pericardium, precluding complete resection to be achieved, primary chemotherapy has been used to reduce the tumour burden, possibly allowing subsequent surgery and/or radiotherapy. Novel strategies are needed, especially for refractory, recurrent tumours and thymic carcinomas, which carry a poor prognosis. Personalised approaches are currently being developed, as potentially “druggable” molecular targets are emerging from recent integrated genomic analyses. Along with the large variety of questions relative to the treatment strategy, thymic epithelial tumours represent a model of therapeutic implementation and achievement in orphan thoracic oncology, showing how the advent of new results induces new questions, as well as diversifies further clinical research directions and international collaborative initiatives.

  1. CT findings of lymphofollicular thymic hyperplasia in adult myasthenia gravis

    International Nuclear Information System (INIS)

    Liu Fugeng; Wei Jiahu; Pan Jishu; Zhou Cheng; Chen Qihang; Yu Jingying; Wu Guogeng; Xu Xianhao

    2006-01-01

    Objective: To evaluate the CT findings of lymphofollicular thymic hyperplasia in adult myasthenia gravis (MG). Methods: The CT findings of thymus area of 134 adult patients with lymphofollicular thymic hyperplasia in MG were reviewed, all of them with surgically and histologically proven diagnosis, and compared with the CT findings of 165 normal subjects. Results: In the group of patient, CT showed enlargement of thymus in 31 patients, 5 patients had nodule or mass ( 3 cm) and 9 patients (6.7%) had normal size thymus with soft-tissue density, it can considered with thymic hyperplasia. The spotty or streak shadow showed in other patients, though it could not be certain diagnosed as thymic hyperplasia, but could not be except it. The thymus area tissue complete replacement by fatty density were not found in patient group. The CT findings of patients had marked difference when compared with group of normal subjects (P<0.01), except the spotty or streak shadows. Conclusion: CT scan is an important method in diagnosing thymic lymphofollicular hyperplasia of MG in adult. (authors)

  2. Fate of thymic radioactivity after local labeling with 125Iododeoxyuridine

    International Nuclear Information System (INIS)

    Laissue, J.A.; Chanana, A.D.; Cottier, H.; Cronkite, E.P.; Joel, D.D.

    1976-01-01

    The thymic cortex was locally labeled with 125 Iododeoxyuridine ( 125 IUdR) in young adult mice in an attempt to provide a simple quantitative assessment of the fate of cortical thymocytes. Similarly operated and nonoperated mice given 125 IUdR intravenously were used for comparison. Analogous experiments were performed in adrenalectomized animals. More than 90 percent of thymic activity present 1 day after labeling had been lost by day 8. That proportion of radioactivity contributed to a given organ by accumulation of labeled thymic migrants was estimated by comparison of values obtained after local labeling with those acquired after systemic labeling. Thymic cell accumulation was apparent in the intestine, spleen, mesenteric lymph node, and femurs of locally labeled mice; however, only a few percent of the total activity lost from the thymus was accounted for in these lymphoid organs. The pattern of fecal and urinary elimination of 125 I did not markedly differ in the various experimental groups, the bulk of the activity being recovered in the urine. The intestine could not be ruled out as a major site of thymocyte loss. Since significant radiation or pharmacologic toxicity was unlikely with the doses of 125 IUdR used, the data indicated that the vast majority of newly formed thymocytes dies after a short life and only a small fraction of thymic migrants is longer lived

  3. Treatment Results and Prognostic Indicators in Thymic Epithelial Tumors: A Clinicopathological Analysis of 45 Patients

    Directory of Open Access Journals (Sweden)

    Mansour Ansari

    2014-07-01

    Full Text Available Background: Thymomas are rare epithelial tumors arising from thymus gland. This study aims at investigating the clinical presentation, prognostic factors and treatment outcome of forty five patients with thymoma and thymic carcinoma. Methods: Forty-five patients being histologically diagnosed with thymoma or thymic carcinoma that were treated and followed-up at a tertiary academic hospital during January 1987 and December 2008 were selected for the present study. Twelve patients were solely treated with surgery, 14 with surgery followed by adjuvant radiotherapy, 12 with sequential combined treatment of surgery, radiotherapy and/or chemotherapy and 7 with non-surgical approach including radiotherapy and/or chemotherapy. Tumors were classified based on the new World Health Organization (WHO histological classification. Results: There were 18 women and 27 men with a median age of 43 years. Twelve patients (26.7% had stage I, 7 (17.8% had stage II, 23 (51% had stage III and 2 (4.5% had stage IV disease. Tumors types were categorized as type A (n=4, type AB (n=10, type B1 (n=9, type B2 (n=10, type B3 (n=5 and type C (n=7. In univariate analysis for overall survival, disease stage (P=0.001, tumor size (P=0.017 and the extent of surgical resection (P<0.001 were prognostic factors. Regarding the multivariate analysis, only the extent of the surgical resection (P<0.001 was the independent prognostic factor and non-surgical treatment had a negative influence on the survival. The 5-year and 10-year overall survival rates were 70.8% and 62.9%, respectively. Conclusion: Complete surgical resection is the most important prognostic factor in patients with thymic epithelial tumors.

  4. Treatment results and prognostic indicators in thymic epithelial tumors: a clinicopathological analysis of 45 patients.

    Science.gov (United States)

    Ansari, Mansour; Dehsara, Farzin; Mohammadianpanah, Mohammad; Mosalaei, Ahmad; Omidvari, Shapour; Ahmadloo, Niloofar

    2014-07-01

    Thymomas are rare epithelial tumors arising from thymus gland. This study aims at investigating the clinical presentation, prognostic factors and treatment outcome of forty five patients with thymoma and thymic carcinoma. Forty-five patients being histologically diagnosed with thymoma or thymic carcinoma that were treated and followed-up at a tertiary academic hospital during January 1987 and December 2008 were selected for the present study. Twelve patients were solely treated with surgery, 14 with surgery followed by adjuvant radiotherapy, 12 with sequential combined treatment of surgery, radiotherapy and/or chemotherapy and 7 with non-surgical approach including radiotherapy and/or chemotherapy.  Tumors were classified based on the new World Health Organization (WHO) histological classification. There were 18 women and 27 men with a median age of 43 years. Twelve patients (26.7%) had stage I, 7 (17.8%) had stage II, 23 (51%) had stage III and 2 (4.5%) had stage IV disease. Tumors types were categorized as type A (n=4), type AB (n=10), type B1 (n=9), type B2 (n=10), type B3 (n=5) and type C (n=7). In univariate analysis for overall survival, disease stage (P=0.001), tumor size (P=0.017) and the extent of surgical resection (P<0.001) were prognostic factors. Regarding the multivariate analysis, only the extent of the surgical resection (P<0.001) was the independent prognostic factor and non-surgical treatment had a negative influence on the survival. The 5-year and 10-year overall survival rates were 70.8% and 62.9%, respectively. Complete surgical resection is the most important prognostic factor in patients with thymic epithelial tumors.

  5. Bioprocessing feasibility analysis. [thymic hormone bioassay and electrophoresis

    Science.gov (United States)

    1978-01-01

    The biology and pathophysiology of the thymus gland is discussed and a clinical procedure for thymic hormone assay is described. The separation of null lymphocytes from mice spleens and the functional characteristics of the cells after storage and transportation were investigated to develop a clinical procedure for thymic hormone assay, and to determine whether a ground-based approach will provide the desired end-product in sufficient quantities, or whether the microgravity of space should be exploited for more economical preparation of the hormone.

  6. Retinoic Acid Signaling in Thymic Epithelial Cells Regulates Thymopoiesis

    DEFF Research Database (Denmark)

    Wendland, Kerstin; Niss, Kristoffer; Kotarsky, Knut

    2018-01-01

    Despite the essential role of thymic epithelial cells (TEC) in T cell development, the signals regulating TEC differentiation and homeostasis remain incompletely understood. In this study, we show a key in vivo role for the vitamin A metabolite, retinoic acid (RA), in TEC homeostasis. In the abse......Despite the essential role of thymic epithelial cells (TEC) in T cell development, the signals regulating TEC differentiation and homeostasis remain incompletely understood. In this study, we show a key in vivo role for the vitamin A metabolite, retinoic acid (RA), in TEC homeostasis...

  7. Antiretroviral therapy increases thymic output in children with HIV

    DEFF Research Database (Denmark)

    Schou Sandgaard, Katrine; Lewis, Joanna; Adams, Stuart

    2014-01-01

    OBJECTIVE: Disease progression and response to antiretroviral therapy (ART) in HIV-infected children is different to that of adults. Immune reconstitution in adults is mainly from memory T cells, whereas in children it occurs predominantly from the naive T-cell pool. It is unclear however what...... with a recently described mathematical model to give explicit measures of thymic output. RESULTS: We found that age-adjusted thymic output is reduced in untreated children with HIV, which increases significantly with length of time on ART. CONCLUSION: Our results suggest that a highly active thymus in early...

  8. Spontaneous rupture of thymic neuroendocrine carcinoma: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan Yeong; Lee, In Jae; Min, Soo Kee [Hallym University College of Medicine, Chuncheon (Korea, Republic of)

    2015-11-15

    Thymic neuroendocrine carcinoma (NEC) is a rare neoplasm with tendencies of local invasion and metastasis. Usually, it is detected incidentally or by its symptoms caused by mass effect. Rupture of the tumor is extremely rare. In this study, we report a case of a ruptured thymic NEC that was combined with a potentially fatal hemorrhage. This lesion was manifested as a progressive bulging of the right cardiac border on serial chest radiographs, and on CT as a large anterior mediastinal mass with heterogeneous enhancement, internal necrosis, and hematoma.

  9. Escape from the Alternative

    Directory of Open Access Journals (Sweden)

    Marin Dinu

    2006-12-01

    Full Text Available This paper sets out to elaborate on Romania’s specific agenda regarding the approach to the integration process in the EU as a project of modernization. The focus is on the functional aspects, the type of strategic solutions destined to consolidate the specific transformations belonging to post-communist transition seen as an internal transition, on the one hand and on the other hand to push convergence as the essence of integration, marked by the vision of EU integration as a continuation of change, which is the stage of external transition. Identifying the prominent factors and the pragmatic priorities of the escape from the peripheries of development by engaging in evolution by way of the second modernization constitutes as well a target for analysis. One particularity of the method of analysis is the review if the value-set of the bobsled effect of path dependency – the path of the peripheries – as well as of the set of values of the escape from the peripheries.

  10. THERMALLY DRIVEN ATMOSPHERIC ESCAPE: TRANSITION FROM HYDRODYNAMIC TO JEANS ESCAPE

    International Nuclear Information System (INIS)

    Volkov, Alexey N.; Johnson, Robert E.; Tucker, Orenthal J.; Erwin, Justin T.

    2011-01-01

    Thermally driven escape from planetary atmospheres changes in nature from an organized outflow (hydrodynamic escape) to escape on a molecule-by-molecule basis (Jeans escape) with increasing Jeans parameter, λ, the ratio of the gravitational to thermal energy of the atmospheric molecules. This change is described here for the first time using the direct simulation Monte Carlo method. When heating is predominantly below the lower boundary of the simulation region, R 0 , and well below the exobase of a single-component atmosphere, the nature of the escape process changes over a surprisingly narrow range of Jeans parameters, λ 0 , evaluated at R 0 . For an atomic gas, the transition occurs over λ 0 ∼ 2-3, where the lower bound, λ 0 ∼ 2.1, corresponds to the upper limit for isentropic, supersonic outflow. For λ 0 > 3 escape occurs on a molecule-by-molecule basis and we show that, contrary to earlier suggestions, for λ 0 > ∼6 the escape rate does not deviate significantly from the familiar Jeans rate. In a gas composed of diatomic molecules, the transition shifts to λ 0 ∼ 2.4-3.6 and at λ 0 > ∼4 the escape rate increases a few tens of percent over that for the monatomic gas. Scaling by the Jeans parameter and the Knudsen number, these results can be applied to thermally induced escape of the major species from solar and extrasolar planets.

  11. An early thymic precursor phenotype predicts outcome exclusively in HOXA-overexpressing adult T-cell acute lymphoblastic leukemia: a Group for Research in Adult Acute Lymphoblastic Leukemia study.

    Science.gov (United States)

    Bond, Jonathan; Marchand, Tony; Touzart, Aurore; Cieslak, Agata; Trinquand, Amélie; Sutton, Laurent; Radford-Weiss, Isabelle; Lhermitte, Ludovic; Spicuglia, Salvatore; Dombret, Hervé; Macintyre, Elizabeth; Ifrah, Norbert; Hamel, Jean-François; Asnafi, Vahid

    2016-06-01

    Gene expression studies have consistently identified a HOXA-overexpressing cluster of T-cell acute lymphoblastic leukemias, but it is unclear whether these constitute a homogeneous clinical entity, and the biological consequences of HOXA overexpression have not been systematically examined. We characterized the biology and outcome of 55 HOXA-positive cases among 209 patients with adult T-cell acute lymphoblastic leukemia uniformly treated during the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-2003 and -2005 studies. HOXA-positive patients had markedly higher rates of an early thymic precursor-like immunophenotype (40.8% versus 14.5%, P=0.0004), chemoresistance (59.3% versus 40.8%, P=0.026) and positivity for minimal residual disease (48.5% versus 23.5%, P=0.01) than the HOXA-negative group. These differences were due to particularly high frequencies of chemoresistant early thymic precursor-like acute lymphoblastic leukemia in HOXA-positive cases harboring fusion oncoproteins that transactivate HOXA Strikingly, the presence of an early thymic precursor-like immunophenotype was associated with marked outcome differences within the HOXA-positive group (5-year overall survival 31.2% in HOXA-positive early thymic precursor versus 66.7% in HOXA-positive non-early thymic precursor, P=0.03), but not in HOXA-negative cases (5-year overall survival 74.2% in HOXA-negative early thymic precursor versus 57.2% in HOXA-negative non-early thymic precursor, P=0.44). Multivariate analysis further revealed that HOXA positivity independently affected event-free survival (P=0.053) and relapse risk (P=0.039) of chemoresistant T-cell acute lymphoblastic leukemia. These results show that the underlying mechanism of HOXA deregulation dictates the clinico-biological phenotype, and that the negative prognosis of early thymic precursor acute lymphoblastic leukemia is exclusive to HOXA-positive patients, suggesting that early treatment intensification is currently

  12. A stromal myoid cell line provokes thymic erythropoiesis between ...

    African Journals Online (AJOL)

    Background: The thymus provides an optimal cellular and humoral microenvironment for cell line committed differentiation of haematopoietic stem cells. The immigration process requires the secretion of at least one peptide called thymotaxine by cells of the reticulo-epithelial (RE) network of the thymic stromal cellular ...

  13. Thymic size at birth in preterm infants with severe respiratory ...

    African Journals Online (AJOL)

    The only maternal and postnatal factors influencing CT/T ratio were the presence of pre-eclamptic toxaemia (PET) and birth by caesarean section (CS), but these factors did not influence likelihood of survival. Factors found to be not associated with thymic size were antenatal steroid administration, maternal HIV status, ...

  14. Thymic size at birth in preterm infants with severe respiratory ...

    African Journals Online (AJOL)

    To determine whether the thymic size in preterm infants with severe respiratory distress syndrome (RDS) can be used to predict ... chorio-amnionitis is associated with a small thymus at birth.4,7. In those ..... Acta Paediatr 2000; 89: 975-978. 6.

  15. Evidence That Androgens Modulate Human Thymic T Cell Output

    Science.gov (United States)

    Olsen, Nancy J.; Kovacs, William J.

    2010-01-01

    Background The thymus has long been recognized as a target for the actions of androgenic hormones, but it has only been recently recognized that alterations in circulating levels of gonadal steroids might affect thymic output of T cells. We had the opportunity to examine parameters of thymic cellular output in several hypogonadal men undergoing androgen replacement therapy. Methods Circulating naive (CD4+CD45RA+) T cells were quantitated by flow cytometric analysis of peripheral blood mononuclear cells (PBMCs). Cells bearing T cell receptor excision circles (TRECs) were quantitated using real-time PCR amplification of DNA isolated from PBMCs from normal men and from hypogonadal men before and after testosterone replacement therapy. Results CD4+CD45+ (“naïve”) T cells comprised 10.5% of lymphocytes in normal males; this proportion was greatly increased in two hypogonadal men (35.5% and 44.4%). One man was studied sequentially during treatment with physiologic doses of testosterone. CD4+CD45RA+ cells fell from 37.36% to 20.05% after one month and to 12.51% after 7 months of normalized androgen levels. In two hypogonadal patients TREC levels fell by 83% and 78% after androgen replacement therapy. Conclusions Our observations indicate that the hypogonadal state is associated with increased thymic output of T cells and that this increase in recent thymic emigrants in peripheral blood is reversed by androgen replacement. PMID:21218609

  16. Expression of tyrosine kinase gene in mouse thymic stromal cells

    NARCIS (Netherlands)

    Rinke de Wit, T. F.; Izon, D. J.; Revilla, C.; Oosterwegel, M.; Bakker, A. Q.; van Ewijk, W.; Kruisbeek, A. M.

    1996-01-01

    Amongst the most important signal transduction molecules involved in regulating growth and differentiation are the protein tyrosine kinases (PTK). Since T cell development is a consequence of interactions between thymic stromal cells (TSC) and thymocytes, identification of the PTK in both

  17. Thymic hyperplasia in a patient with Grave's disease.

    Science.gov (United States)

    Hamzaoui, Amira A; Klii, Rim R; Salem, Randa R; Kochtali, Ines I; Golli, Mondher M; Mahjoub, Silvia S

    2012-02-09

    Hyperplastic changes of the thymus may be found in patients with Graves' disease. However, this rarely presents as an anterior mediastinal mass, particularly among adults. In this report, we describe a 46-year old woman with Graves' disease and thymic hyperplasia.

  18. Thymic hyperplasia in a patient with Grave's disease

    Directory of Open Access Journals (Sweden)

    Hamzaoui Amira A

    2012-02-01

    Full Text Available Abstract Hyperplastic changes of the thymus may be found in patients with Graves' disease. However, this rarely presents as an anterior mediastinal mass, particularly among adults. In this report, we describe a 46-year old woman with Graves' disease and thymic hyperplasia.

  19. IL-33 and Thymic Stromal Lymphopoietin in mast cell functions

    NARCIS (Netherlands)

    Saluja, Rohit; Zoltowska, Anna; Ketelaar, Maria Elizabeth; Nilsson, Gunnar

    2016-01-01

    Thymic Stromal Lymphopoietin (TSLP) and Interleukin 33 (IL-33) are two cytokines released by cells that are in proximity to our environment, e.g., keratinocytes of the skin and epithelial cells of the airways. Pathogens, allergens, chemicals and other agents induce the release of TSLP and IL-33,

  20. Hydrodynamic escape from planetary atmospheres

    Science.gov (United States)

    Tian, Feng

    Hydrodynamic escape is an important process in the formation and evolution of planetary atmospheres. Due to the existence of a singularity point near the transonic point, it is difficult to find transonic steady state solutions by solving the time-independent hydrodynamic equations. In addition to that, most previous works assume that all energy driving the escape flow is deposited in one narrow layer. This assumption not only results in less accurate solutions to the hydrodynamic escape problem, but also makes it difficult to include other chemical and physical processes in the hydrodynamic escape models. In this work, a numerical model describing the transonic hydrodynamic escape from planetary atmospheres is developed. A robust solution technique is used to solve the time dependent hydrodynamic equations. The method has been validated in an isothermal atmosphere where an analytical solution is available. The hydrodynamic model is applied to 3 cases: hydrogen escape from small orbit extrasolar planets, hydrogen escape from a hydrogen rich early Earth's atmosphere, and nitrogen/methane escape from Pluto's atmosphere. Results of simulations on extrasolar planets are in good agreement with the observations of the transiting extrasolar planet HD209458b. Hydrodynamic escape of hydrogen from other hypothetical close-in extrasolar planets are simulated and the influence of hydrogen escape on the long-term evolution of these extrasolar planets are discussed. Simulations on early Earth suggest that hydrodynamic escape of hydrogen from a hydrogen rich early Earth's atmosphere is about two orders magnitude slower than the diffusion limited escape rate. A hydrogen rich early Earth's atmosphere could have been maintained by the balance between the hydrogen escape and the supply of hydrogen into the atmosphere by volcanic outgassing. Origin of life may have occurred in the organic soup ocean created by the efficient formation of prebiotic molecules in the hydrogen rich early

  1. Sonographic measurement of thymic size in healthy Korean neonates

    International Nuclear Information System (INIS)

    Seo, Hyun Joo; Yoon, Dae Young; Han, Dae Hee; Han, Sang Wook; Kim, Ho Chul; Kim, Young Mook; Choi, Chul Soon; Bae, Sang Hoon

    2001-01-01

    To assess the variation in thymic size in healthy Korean neonates by sonography and to study the possible correlation to clinical variables. This study was made of 112 healthy Korean neonates (94 full-term and 18 preterm), at less than a week of age. The transverse diameter of the thymus was measured in a transverse scan and the largest sagittal area was assessed in a longitudinal scan. The thymic index was defined as the product of these two values. Then, this index was compared to clinical variables, such as sex, delivery method (spontaneous delivery vs cesarian section), body weight, height, body surface area, head circumference, chest circumference, gestational age, and maternal age in both full-term and preterm groups. The thymic index was 9.6 ± 3.1 (range 3.1-20.2) in full-term and 4.2 ± 2.4 (range 0.9-9.9) in preterm neonates, respectively. The thymic index was positively correlated to the body weight (R=0.550 in full-term, R=0.669 in preterm) and body surface area (R=0.540 in full-term, R=0.674 in preterm) in both full-term and preterm groups (p<0.01). There was no statistically significant correlation to sex, delivery method, height, head circumference, chest circumference, maternal age or gestational age. The thymic index in Healthy Korean neonates as measured by sonography is significantly correlated to the body weight and body surface area of the neonate.

  2. The effects of escape from self and interpersonal relationship on the pathological use of Internet games.

    Science.gov (United States)

    Kwon, Jung-Hye; Chung, Chung-Suk; Lee, Jung

    2011-02-01

    The purpose of the present study was to examine whether Baumeister's escape from self theory may account for the pathological use of Internet games among Korean adolescents. A sample of 1,136 junior high school students completed measures assessing Internet game addiction (IGA), real-ideal self discrepancy, escape from self, current mood, peer relationships, perceived parent-child relationship, and parental supervision. IGA was significantly correlated with all of these variables. Multiple regression analysis showed that escape from self best explained the adolescents' IGA. A path model yielded significant paths from self-discrepancy to negative mood, from negative mood to escape from self, and from escape from self to IGA. These results support the validity of using the escape from self theory to explain the adolescents' IGA, thereby suggesting that adolescents become addicted to Internet games in an attempt to escape from self and reality.

  3. Evaluation of thymic tumors with 18F-FDG PET-CT - A pictorial review

    International Nuclear Information System (INIS)

    Sharma, Punit; Singhal, Abhinav; Bal, Chandrasekhar; Malhotra, Arun; Kumar, Rakesh; Kumar, Arvind

    2013-01-01

    Thymic tumors represent a broad spectrum of neoplastic disorders and pose considerable diagnostic difficulties. A non-invasive imaging study to determine the nature of thymic lesions can have significant impact on management of such tumors. 18F-flurorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) has shown promising results in characterization of thymic tumors. The objective of this article is to provide an illustrative tutorial highlighting the clinical utility of 18F-FDG PET-CT imaging in patients with thymic tumors. We have pictorially depicted the 18F-FDG PET-CT salient imaging characteristics of various thymic tumors, both epithelial and non-epithelial. Also discussed is the dynamic physiology of thymus gland which is to be kept in mind when evaluating thymic pathology on 18F-FDG PET-CT, as it can lead to interpretative pitfalls

  4. LAT1 acts as a crucial transporter of amino acids in human thymic carcinoma cells

    Directory of Open Access Journals (Sweden)

    Keitaro Hayashi

    2016-11-01

    Full Text Available L-type amino acid transporter 1 (LAT1, SLC7A5 incorporates essential amino acids into cells. Recent studies have shown that LAT1 is a predominant transporter in various human cancers. However, the function of LAT1 in thymic carcinoma remains unknown. Here we demonstrate that LAT1 is a critical transporter for human thymic carcinoma cells. LAT1 was strongly expressed in human thymic carcinoma tissues. LAT1-specific inhibitor significantly suppressed leucine uptake and growth of Ty82 human thymic carcinoma cell lines, suggesting that thymic carcinoma takes advantage of LAT1 as a quality transporter and that LAT1-specific inhibitor might be clinically beneficial in therapy for thymic carcinoma.

  5. Clinical results of radiation therapy for thymic tumors

    Energy Technology Data Exchange (ETDEWEB)

    Masunaga, Shin-ichiro; Ono, Koji; Hiraoka, Masahiro; Kitakabu, Yoshizumi; Abe, Mitsuyuki (Kyoto Univ. (Japan). Faculty of Medicine); Takahashi, Masaji; Fushiki, Masato

    1991-12-01

    From August 1968 to December 1989, 58 patients with thymoma, and 3 with thymic carcinoma were treated by radiotherapy using cobalt-60 gamma ray. Eleven cases were treated by radiotherapy alone, 1 by preoperative radiotherapy, 45 by postoperative radiotherapy, and 4 in combination with intraoperative radiotherapy. In thymoma, postoperative and intraoperative radiotherapies were effective, while concerning postoperative radiotherapy, operability was the major factor influencing survival and local control, and Stage I and II tumors resected totally or subtotally as well as Stage III tumors resected totally were good indications for such therapy. Cases of thymoma complicated by myasthenia gravis had a longer survival time and better local control rate than those without it. In the treatment of thymic carcinoma, it was suggested that the tumors can be controlled using complete resection and sufficient postoperative radiotherpay. (author).

  6. Clinical results of radiation therapy for thymic tumors

    International Nuclear Information System (INIS)

    Masunaga, Shin-ichiro; Ono, Koji; Hiraoka, Masahiro; Kitakabu, Yoshizumi; Abe, Mitsuyuki; Takahashi, Masaji; Fushiki, Masato.

    1991-01-01

    From August 1968 to December 1989, 58 patients with thymoma, and 3 with thymic carcinoma were treated by radiotherapy using cobalt-60 gamma ray. Eleven cases were treated by radiotherapy alone, 1 by preoperative radiotherapy, 45 by postoperative radiotherapy, and 4 in combination with intraoperative radiotherapy. In thymoma, postoperative and intraoperative radiotherapies were effective, while concerning postoperative radiotherapy, operability was the major factor influencing survival and local control, and Stage I and II tumors resected totally or subtotally as well as Stage III tumors resected totally were good indications for such therapy. Cases of thymoma complicated by myasthenia gravis had a longer survival time and better local control rate than those without it. In the treatment of thymic carcinoma, it was suggested that the tumors can be controlled using complete resection and sufficient postoperative radiotherpay. (author)

  7. Thyroid and thymic exeresis in surgery of hyperparathyroidism.

    Science.gov (United States)

    Diaconescu, Mr; Glod, M; Costea, I; Grigorovici, M; Diaconescu, S

    2014-01-01

    Owing to close anatomical and embryological connexions between the thyroid, parathyroids and thymus,manifold coexisting pathology can be identified during the surgery of hyperparathyroidism (Hp). In this retrospective study we report the incidence, clinical forms, histology and management of thyroid and thymic synchronous lesions encountered in as eries of 82 consecutive patients with various types of Hp operated on in the last three decades. Demography, clinical records, biochemical data, imaging procedures, pathology reports and surgical protocols were revised. Between 1984-2013, 82 cases of Hp, 20 primary and 62 renal (27 secondary and 35 tertiary), 57 women and 25 males (sex ratio: 2.3 1) of 15-72 (mean 46.5) years, under went surgery in our clinic. Concomitant thyroid exereses were performed in 32 patients (2 subtotal thyroidectomies, 12 lobectomies, 8 atypical resections and 10 diagnosis biopsies), foruni- or bilateral (multi)nodular goiters or different €œminutelesions. Pathology showed 11 colloid goiters, 3 follicular adenomas,5 nodular hyperplasias and 6 thyroiditis cases, 3 papillary microcarcinomas and 4 specimens with normal thyroid tissue.Excision of the fibrofatty retromanubrial tissue in total parathyroidectomies for renal Hp (19 cases) revealed one nonmyastenicthymoma, one thymic cyst and thymic remnants in 6 patients.Morbidity in these extended operations was not significantly increased, comparing to the parathyroid exploration alone. Meticulous pre- and intraoperative evaluation in all cases of Hp enables the actual shift from bilateral neck exploration to minimally invasive surgery,increasing however the potential risk of missing thyroid or thymic coexistent significant lesions. The surgeon dedicated to this pathology must be aware of the possibility of encountering such synchronous association and make generous efforts to wards their complete cure in a single operation. Celsius.

  8. Effects of the thymic microenvironment on autoantibody production in (NZB X NZW)F1 mice

    International Nuclear Information System (INIS)

    Huston, D.P.; Smathers, P.A.; Reeves, J.P.; Steinberg, A.D.

    1983-01-01

    The effects of the thymic microenvironment on autoantibody production in (NZB X NZW)F1 mice were studied. Neonatally thymectomized male and female F1 mice reconstituted with a parental or F1-irradiated thymic lobe were compared to nonreconstituted and sham-thymectomized controls. While maleness retarded the spontaneous production of ss- and ds-DNA antibodies, thymic grafts did not suppress antibodies to ss-DNA in either sex, but did suppress the production of antibodies to ds-DNA in female mice. A unique property of NZB thymic grafts was the inability to suppress anti-RBC antibodies in male mice. Thus, (i) the gender of the F1 recipient was the most important determinant of production of antibodies to ss-DNA, (ii) either maleness or the thymic microenvironment could retard production of anti-ds-DNA antibodies, and (iii) both gender and the thymic microenvironment were important in the regulation of anti-RBC antibody production. Since the administration of thymosin did not suppress autoantibody production, the effects of the thymic grafts was not solely via thymic hormone production. These studies suggest that sex hormones and/or the thymic microenvironment can exert a suppressive effect on autoantibody production and that autoantibodies differ in their susceptibility to such suppression

  9. [Impact of thymic function in age-related immune deterioration].

    Science.gov (United States)

    Ferrando-Martínez, Sara; de la Fuente, Mónica; Guerrero, Juan Miguel; Leal, Manuel; Muñoz-Fernández, M Ángeles

    2013-01-01

    Age-related biological deterioration also includes immune system deterioration and, in consequence, a rise in the incidence and prevalence of infections and cancers, as well as low responses to vaccination strategies. Out of all immune cell subsets, T-lymphocytes seem to be involved in most of the age-related defects. Since T-lymphocytes mature during their passage through the thymus, and the thymus shows an age-related process of atrophy, thymic regression has been proposed as the triggering event of this immune deterioration in elderly people. Historically, it has been accepted that the young thymus sets the T-lymphocyte repertoire during the childhood, whereupon atrophy begins until the elderly thymus is a non-functional evolutionary trace. However, a rising body of knowledge points toward the thymus functioning during adulthood. In the elderly, higher thymic function is associated with a younger immune system, while thymic function failure is associated with all-cause mortality. Therefore, any new strategy focused on the improvement of the elderly quality of life, especially those trying to influence the immune system, should take into account, together with peripheral homeostasis, thymus function as a key element in slowing down age-related decline. Copyright © 2012 SEGG. Published by Elsevier Espana. All rights reserved.

  10. [Thymic carcinoma involving aortic arch; report of a case].

    Science.gov (United States)

    Noriyuki, Toshio; Hamamoto, M; Takazawa, Y; Katoh, K; Hashimoto, M; Kuranishi, F; Nakahara, M; Fukuda, T; Ishizaki, Y; Okuda, H; Akimoto, E; Yonehara, S

    2009-05-01

    Adenocarcinoma of the thymus is a very rare malignant tumor. The standard treatment for advanced thymic carcinoma has not yet been established, and the prognosis is poor. We report a case of thymic carcinoma that involving the aortic arch and the innominate vein. A 78-year-old woman was admitted to our hospital complaining of hoarseness in April 2007. The computed tomography (CT) scan showed an anterior mediastinal tumor contiguous to the aortic arch and the innominate vein with swelling lymphnodes. Microspcopic examinations of specimens obtained by CT-guided needle biopsy revealed poorly differenciated adenocarcinoma. The carcinoembryonic antigen (CEA) level of serum elevated at 54.9 ng/ml. Thymic carcinoma was diagnosed. The chemoradiotherapy [concurrent, carboplatin (CBDCA) + paclitaxel(TXL)-->vinorelbine (NVB), 60 Gy] was performed, but the effect of the therapy was limited. The resection of the tumor with a part of aortic arch and other peripheral tissues was performed in Augast 2007. The postoperative course was uneventful and the CEA level of serum lowered to the normal. She was discharged 30 days after surgery.

  11. Creating Engaging Escape Rooms for the Classroom

    Science.gov (United States)

    Nicholson, Scott

    2018-01-01

    Escape rooms are "live-action team-based games where players discover clues, solve puzzles, and accomplish tasks in one or more rooms in order to accomplish a specific goal (usually escaping from the room) in a limited amount of time." Escape Rooms are one type of Escape Game, which are narrative-based challenges that use puzzles, tasks,…

  12. Interaction between thymic cells and hemopoietic stem cells. Enhanced repopulation of the irradiated thymus

    International Nuclear Information System (INIS)

    Daculsi, Richard; Legrand, Elisabeth; Duplan, J.-F.

    1977-01-01

    In irradiated mice engrafted with hemopoietic cells, the thymus is repopulated more rapidly by bone marrow-derived than by spleen-derived cells. Admixing thymic cells with restorative suspension stimulates the thymic repopulation by spleen-derived cells whereas it has no effect on the repopulation by bone marrow-derived cells [fr

  13. Prosthetic Mitral Valve Leaflet Escape

    Science.gov (United States)

    Kim, Darae; Hun, Sin Sang; Cho, In-Jeong; Shim, Chi-Young; Ha, Jong-Won; Chung, Namsik; Ju, Hyun Chul; Sohn, Jang Won

    2013-01-01

    Leaflet escape of prosthetic valve is rare but potentially life threatening. It is essential to make timely diagnosis in order to avoid mortality. Transesophageal echocardiography and cinefluoroscopy is usually diagnostic and the location of the missing leaflet can be identified by computed tomography (CT). Emergent surgical correction is mandatory. We report a case of fractured escape of Edward-Duromedics mitral valve 27 years after the surgery. The patient presented with symptoms of acute decompensated heart failure and cardiogenic shock. She was instantly intubated and mechanically ventilated. After prompt evaluation including transthoracic echocardiography and CT, the escape of the leaflet was confirmed. The patient underwent emergent surgery for replacement of the damaged prosthetic valves immediately. Eleven days after the surgery, the dislodged leaflet in iliac artery was removed safely and the patient recovered well. PMID:23837121

  14. Automated Escape Guidance Algorithms for An Escape Vehicle

    Science.gov (United States)

    Flanary, Ronald; Hammen, David; Ito, Daigoro; Rabalais, Bruce; Rishikof, Brian; Siebold, Karl

    2002-01-01

    An escape vehicle was designed to provide an emergency evacuation for crew members living on a space station. For maximum escape capability, the escape vehicle needs to have the ability to safely evacuate a station in a contingency scenario such as an uncontrolled (e.g., tumbling) station. This emergency escape sequence will typically be divided into three events: The fust separation event (SEP1), the navigation reconstruction event, and the second separation event (SEP2). SEP1 is responsible for taking the spacecraft from its docking port to a distance greater than the maximum radius of the rotating station. The navigation reconstruction event takes place prior to the SEP2 event and establishes the orbital state to within the tolerance limits necessary for SEP2. The SEP2 event calculates and performs an avoidance burn to prevent station recontact during the next several orbits. This paper presents the tools and results for the whole separation sequence with an emphasis on the two separation events. The fust challenge includes collision avoidance during the escape sequence while the station is in an uncontrolled rotational state, with rotation rates of up to 2 degrees per second. The task of avoiding a collision may require the use of the Vehicle's de-orbit propulsion system for maximum thrust and minimum dwell time within the vicinity of the station vicinity. The thrust of the propulsion system is in a single direction, and can be controlled only by the attitude of the spacecraft. Escape algorithms based on a look-up table or analytical guidance can be implemented since the rotation rate and the angular momentum vector can be sensed onboard and a-priori knowledge of the position and relative orientation are available. In addition, crew intervention has been provided for in the event of unforeseen obstacles in the escape path. The purpose of the SEP2 burn is to avoid re-contact with the station over an extended period of time. Performing this maneuver properly

  15. Anti-apoptotic signature in thymic squamous cell carcinomas – functional relevance of anti-apoptotic BIRC3 expression in the thymic carcinoma cell line 1889c

    OpenAIRE

    Huang, Bei; Belharazem, Djeda; Li, Li; Kneitz, Susanne; Schnabel, Philipp A.; Rieker, Ralf J.; Körner, Daniel; Nix, Wilfried; Schalke, Berthold; Müller-Hermelink, Hans Konrad; Ott, German; Rosenwald, Andreas; Ströbel, Philipp; Marx, Alexander

    2016-01-01

    The molecular pathogenesis of thymomas and thymic carcinomas (TCs) is poorly understood and results of adjuvant therapy are unsatisfactory in case of metastatic disease and tumor recurrence. For these clinical settings, novel therapeutic strategies are urgently needed. Recently, limited sequencing efforts revealed that a broad spectrum of genes that play key roles in various common cancers are rarely affected in thymomas and thymic carcinomas, suggesting that other oncogenic principles might ...

  16. Radiotherapy for invasive thymoma and thymic carcinoma. Clinicopathological review

    International Nuclear Information System (INIS)

    Mayer, R.; Stuecklschweiger, G.F.; Prettenhofer, U.; Stranzl, H.; Hackl, A.; Beham-Schmid, C.; Groell, R.; Smolle-Juettner, F.M.; Renner, H.; Quehenberger, F.

    1999-01-01

    All 33 patients were irradiated with a mean dose of 50 Gy after complete resection (16 patients), partial resection (9 patients) of biopsy (8 patients). Staging was done according to the Masaoka classification; there were 12 Stage II, 12 Stage III and 9 Stage IV patients. Results: In patients with invasive thymoma Stage II to IV (median follow-up 54.4 months) Kaplan-Meier estimates of overall survival (OS), disease-specific (DSS) and disease-free survival (DFS) at 5 years were 63.7% (95% confidence interval [CI], 42 to 84%), 88.3% (CI, 75 to 100%) and 77,4% (CI, 58 to 95%), respectively. Among the prognostic factors tested, such as age, myasthenia gravis, completeness of surgery and histologic subclassification, total radiation dose, and Masaoka Stage, the latter was the only significant predictor of improved survival (p=0.04). Considering local control, radiation dose was a significant prognostic factor (p=0.0006). In patients with thymic carcinoma (median follow-up 43.4 months) 5 year DSS, and DFS were 22.2% (CI, 0 to 60%) and 16.7% (CI, 0 to 46%), respectively. Thymoma as compared to thymic carcinoma had a statistically significant better DSS (p=0.007) and DFS (p=0.0007). Conclusion: Postoperative radiotherapy with sufficient doses plays an important role as adjuvant treatment in complete or incomplete resected invasive Stage II to III thymoma. In unresectable thymoma Stage III to IV as well as in thymic carcinoma a multimodality approach should be considered to improve survival. (orig.) [de

  17. Immunologic competence in adults following thymic irradiation in infancy

    International Nuclear Information System (INIS)

    Ammann, A.J.; Wara, W.M.; Wara, D.W.; Phillips, T.L.

    1977-01-01

    Removal of, or irradiation to, the thymus during the neonatal period in man has resulted in no reported adverse effects on cellular immunity, although thymectomy in neonatal experimental animals is known to produce profound immunological disturbances. Adverse effects in humans may not be recognized until several decades have passed. The immunological capabilities of 7 adults with histories of thymic irradiation as infants were evaluated; normal tests results indicated intact immune systems in all cases. The 3 women tested, however, had abnormal clinical histories, including 2 with multiple tumors and 1 with chronic mucocutaneous candidiasis

  18. Human thymic epithelial cells express functional HLA-DP molecules

    DEFF Research Database (Denmark)

    Jørgensen, A; Röpke, C; Nielsen, M

    1996-01-01

    T lymphocytes, we examined whether human thymic epithelial cells (TEC) expressed HLA-DP molecules. We present evidence that TEC obtained from short time culture express low but significant levels of HLA-DP molecules. The expression of HLA-DP molecules was comparable to or higher than the expression...... of HLA-DP allospecific primed lymphocyte typing (PLT) CD4 T cell lines. IFN-gamma treatment strongly upregulated the HLA-DP allospecific PLT responses whereas other PLT responses remained largely unchanged. In conclusion, these data indicate that human thymus epithelial cells express significant levels...

  19. Immunologic competence in adults following thymic irradiation in infancy

    Energy Technology Data Exchange (ETDEWEB)

    Ammann, A.J.; Wara, W.M.; Wara, D.W.; Phillips, T.L.

    1977-07-01

    Removal of, or irradiation to, the thymus during the neonatal period in man has resulted in no reported adverse effects on cellular immunity, although thymectomy in neonatal experimental animals is known to produce profound immunological disturbances. Adverse effects in humans may not be recognized until several decades have passed. The immunological capabilities of 7 adults with histories of thymic irradiation as infants were evaluated; normal tests results indicated intact immune systems in all cases. The 3 women tested, however, had abnormal clinical histories, including 2 with multiple tumors and 1 with chronic mucocutaneous candidiasis.

  20. Modulatory effects of cAMP and PKC activation on gap junctional intercellular communication among thymic epithelial cells

    Directory of Open Access Journals (Sweden)

    Neves-dos-Santos Sandra

    2010-01-01

    Full Text Available Abstract Background We investigated the effects of the signaling molecules, cyclic AMP (cAMP and protein-kinase C (PKC, on gap junctional intercellular communication (GJIC between thymic epithelial cells (TEC. Results Treatment with 8-Br-cAMP, a cAMP analog; or forskolin, which stimulates cAMP production, resulted in an increase in dye transfer between adjacent TEC, inducing a three-fold enhancement in the mean fluorescence of coupled cells, ascertained by flow cytometry after calcein transfer. These treatments also increased Cx43 mRNA expression, and stimulated Cx43 protein accumulation in regions of intercellular contacts. VIP, adenosine, and epinephrine which may also signal through cyclic nucleotides were tested. The first two molecules did not mimic the effects of 8-Br-cAMP, however epinephrine was able to increase GJIC suggesting that this molecule functions as an endogenous inter-TEC GJIC modulators. Stimulation of PKC by phorbol-myristate-acetate inhibited inter-TEC GJIC. Importantly, both the enhancing and the decreasing effects, respectively induced by cAMP and PKC, were observed in both mouse and human TEC preparations. Lastly, experiments using mouse thymocyte/TEC heterocellular co-cultures suggested that the presence of thymocytes does not affect the degree of inter-TEC GJIC. Conclusions Overall, our data indicate that cAMP and PKC intracellular pathways are involved in the homeostatic control of the gap junction-mediated communication in the thymic epithelium, exerting respectively a positive and negative role upon cell coupling. This control is phylogenetically conserved in the thymus, since it was seen in both mouse and human TEC preparations. Lastly, our work provides new clues for a better understanding of how the thymic epithelial network can work as a physiological syncytium.

  1. Thymic size in uninfected infants born to HIV-positive mothers and fed with pasteurized human milk.

    Science.gov (United States)

    Jeppesen, D; Hasselbalch, H; Ersbøll, A K; Heilmann, C; Valerius, N H

    2003-06-01

    To examine the size of the thymus in uninfected infants born to HIV-positive mothers and to study the effects of feeding by human donor milk on the size of the thymus in these infants. The absolute and relative thymic size was assessed by sonography as thymic index (Ti), and the Ti/weight-ratio (Ti/w) at birth and at 4 mo of age in 12 healthy uninfected infants born to HlV-infected mothers. All infants were exclusively fed pasteurized donor milk. The results were compared with those obtained from a previous cohort of exclusively breastfed, partially breastfed and exclusively formula-fed infants. At birth the Ti was reduced in infants born to HIV-infected mothers in comparison with that in control infants but this difference disappeared when their birthweights were taken into consideration (Ti/w-ratio). At 4 mo of age the geometric mean Ti of infants fed donor milk was 23.8 and the mean Ti/w-ratio was 4.2. Compared with those of exclusively breastfed infants, the Ti and Ti/w-ratio of infants fed donor milk were significantly reduced (p milk-fed infants compared with that in the formula-fed infants (p = 0.02). At birth the size of the thymus was smaller in uninfected infants of HIV-positive mothers compared with infants of HIV-negative mothers but when birthweight was taken into account this difference disappeared. Feeding by human donor milk seemed to result in an increased size of the thymus at 4 mo of age compared with thymic size in infants that were exclusively formula fed.

  2. Cnidoscolus (Euphorbiaceae) escaped in Malesia?

    NARCIS (Netherlands)

    Welzen, van P.C.; Fernández-Casas, F.J.

    2017-01-01

    The genus Cnidoscolus, a species rich genus in the Americas, has been introduced in the Philippines. A cultivar of Cnidoscolus aconitifolius is used as vegetable and has been collected from gardens in Manila and Pasay City and two times near Cebu City. It cannot be excluded that it has escaped

  3. Generation of Tumor Antigen-Specific iPSC-Derived Thymic Emigrants Using a 3D Thymic Culture System

    Directory of Open Access Journals (Sweden)

    Raul Vizcardo

    2018-03-01

    Full Text Available Summary: Induced pluripotent stem cell (iPSC-derived T cells may provide future therapies for cancer patients, but those generated by current methods, such as the OP9/DLL1 system, have shown abnormalities that pose major barriers for clinical translation. Our data indicate that these iPSC-derived CD8 single-positive T cells are more like CD4+CD8+ double-positive T cells than mature naive T cells because they display phenotypic markers of developmental arrest and an innate-like phenotype after stimulation. We developed a 3D thymic culture system to avoid these aberrant developmental fates, generating a homogeneous subset of CD8αβ+ antigen-specific T cells, designated iPSC-derived thymic emigrants (iTEs. iTEs exhibit phenotypic and functional similarities to naive T cells both in vitro and in vivo, including the capacity for expansion, memory formation, and tumor suppression. These data illustrate the limitations of current methods and provide a tool to develop the next generation of iPSC-based antigen-specific immunotherapies. : A barrier for clinical application of iPSC-derived CD8 T cells using OP9/DLL1 is their abnormal biology. Vizcardo et al. show that a 3D thymic culture system enables the generation of a homogeneous antigen-specific T cell subset, named iTEs, which closely mimics naive T cells and exhibits potent anti-tumor activity. Keywords: thymopoiesis, T cell differentiation, iPSC differentiation, adoptive cell transfer, naïve T cell, recent rhymic emigrants, fetal thymus organ culture, immunotherapy, 3D culture, tumor antigen specific T cell

  4. Flt3 ligand-receptor interaction is important for maintenance of early thymic progenitor numbers in steady-state thymopoiesis.

    Science.gov (United States)

    Kenins, Linda; Gill, Jason W; Holländer, Georg A; Wodnar-Filipowicz, Aleksandra

    2010-01-01

    T-cell production throughout life depends on efficient colonization and intrathymic expansion of BM-derived hematopoietic precursors. After irradiation-induced thymic damage, thymic recovery is facilitated by Flt3 ligand (FL), expressed by perivascular fibroblasts surrounding the thymic entry site of Flt3 receptor-positive progenitor cells. Whether intrathymic FL-Flt3 interactions play a role in steady-state replenishment of T cells remains unknown. Here, using competitive BM transplantation studies and fetal thymic organ cultures we demonstrated the continued numerical advantage of Flt3+ intrathymic T-cell precursors. Sub-kidney capsule thymic transplantation experiments, in which WT and FL-/- thymic lobes were grafted into FL-/- recipients, revealed that FL expression by the thymic microenvironment plays a role in steady-state thymopoiesis. The deficiency of the most immature thymic T-cell precursors correlated to upregulation of FL by thymic MTS15+ fibroblasts, suggesting that the number of Flt3+ progenitor cells may regulate the thymic expression of this cytokine. Together, these results show that FL expression by thymic stromal fibroblasts interacting with Flt3+ T-cell progenitors is important for the physiological maintenance of early T-cell development.

  5. On the relative contributions of positive reinforcement and escape extinction in the treatment of food refusal.

    Science.gov (United States)

    Piazza, Cathleen C; Patel, Meeta R; Gulotta, Charles S; Sevin, Bari M; Layer, Stacy A

    2003-01-01

    We compared the effects of positive reinforcement alone, escape extinction alone, and positive reinforcement with escape extinction in the treatment of the food and fluid refusal of 4 children who had been diagnosed with a pediatric feeding disorder. Consumption did not increase when positive reinforcement was implemented alone. By contrast, consumption increased for all participants when escape extinction was implemented, independent of the presence or absence of positive reinforcement. However, the addition of positive reinforcement to escape extinction was associated with beneficial effects (e.g., greater decreases in negative vocalizations and inappropriate behavior) for some participants.

  6. Reactive thymic hyperplasia following treatment of ACTH-producing tumors

    International Nuclear Information System (INIS)

    Schmidt, S.; Klose, K.J.; Iwinska-Zelder, J.; Frank, M.; Ehlenz, K.; Kisker, O.

    1997-01-01

    Surgical or conservative treatment of ACTH-producing tumors results in acute drop of the previously excessively high cortisol levels. The following associated pathophysiological changes also occur in the organism's recovery from stress, such as trauma, operation or chemotherapy of tumors. Both cases result in a regeneration of the immune system, which might even be exalted. The corresponding radiographic feature is the 'rebound' enlargement of the thymus occuring about six months after remission of hypercortisolism. Histological examination reveals benign thymus hyperplasia. Especially in cases of still unkown primary tumor the apperance of this anterior mediastinal mass can lead to misdiagnosis. We present the cases of two patients with diffuse thymic hyperplasia following surgical and medical correction of hypercortisolism. One patient suffered from classic Cushing's disease responding to transsphenoidal resection of an ACTH-secreting pituitary microadenoma. Six monsths later CT of the chest incidentally demonstrated an anterior mediastinal mass known as thymic hyperplasia. The second patient presented with an ectopic, still unknown source of ACTH-production. (orig./AJ) [de

  7. Mutational status of EGFR and KIT in thymoma and thymic carcinoma.

    Science.gov (United States)

    Yoh, Kiyotaka; Nishiwaki, Yutaka; Ishii, Genichiro; Goto, Koichi; Kubota, Kaoru; Ohmatsu, Hironobu; Niho, Seiji; Nagai, Kanji; Saijo, Nagahiro

    2008-12-01

    This study was conducted to evaluate the prevalence of EGFR and KIT mutations in thymomas and thymic carcinomas as a means of exploring the potential for molecularly targeted therapy with tyrosine kinase inhibitors. Genomic DNA was isolated from 41 paraffin-embedded tumor samples obtained from 24 thymomas and 17 thymic carcinomas. EGFR exons 18, 19, and 21, and KIT exons 9, 11, 13, and 17, were analyzed for mutations by PCR and direct sequencing. Protein expression of EGFR and KIT was evaluated immunohistochemically. EGFR mutations were detected in 2 of 20 thymomas, but not in any of the thymic carcinomas. All of the EGFR mutations detected were missense mutations (L858R and G863D) in exon 21. EGFR protein was expressed in 71% of the thymomas and 53% of the thymic carcinomas. The mutational analysis of KIT revealed only a missense mutation (L576P) in exon 11 of one thymic carcinoma. KIT protein was expressed in 88% of the thymic carcinomas and 0% of the thymomas. The results of this study indicate that EGFR and KIT mutations in thymomas and thymic carcinomas are rare, but that many of the tumors express EGFR or KIT protein.

  8. Clinical analysis of thymic regrowth following chemotherapy in children and adolescents with malignant lymphoma

    International Nuclear Information System (INIS)

    Zhen Zijun; Sun Xiaofei; Xia Yi; Ling Jiayu; Cai Yue; Wang Juan; Guan Zhongzhen

    2010-01-01

    Thymic regrowth following chemotherapy has typical clinical and imaging manifestations that can be used to diagnose it prior to pathological diagnosis. We investigated methods for diagnosing thymic regrowth following chemotherapy with non-invasive methods. Our study included 26 children and adolescents with thymic regrowth following chemotherapy for malignant lymphoma. Computed tomography scans were routinely performed for follow-up observations. After the emergence of new mediastinal masses, patients either underwent Fluorine-18 fluorodeoxyglucose-positron emission tomography scans to identify the characteristics of the mass, or were closely followed up. Thymic regrowth occurred 1-12 months after the last chemotherapy (mean, 4 months). Computed tomography mostly revealed diffusely enlarged thymic parenchymatous tissues that maintained normal thymic morphology. Computed tomography values were 36.72±9.48 Hu and increased by 5.56±2.62 Hu in contrast enhancement. The mean volume of the mass was 19.2 cm 3 . Twenty patients underwent positron emission tomography; among them, five (25%) showed no intake of Fluorine-18 fluorodeoxyglucose in the anterior mediastinal mass, and 15 (75%) showed radioactivity distribution in the mass with a mean standardized uptake value of 2.7; the shape was regular and radioactivity distribution was uniform. The mean follow-up duration was 40 months and all patients achieved disease-free survival. In the absence of pathological diagnosis, thymic regrowth following chemotherapy can be diagnosed by clinical features combined with characteristic manifestations in computed tomography and positron emission tomography scans. (author)

  9. Thymic epithelial tumors: Comparison of CT and MR imaging findings of low-risk thymomas, high-risk thymomas, and thymic carcinomas

    International Nuclear Information System (INIS)

    Sadohara, Junko; Fujimoto, Kiminori; Mueller, Nestor L.; Kato, Seiya; Takamori, Shinzo; Ohkuma, Kazuaki; Terasaki, Hiroshi; Hayabuchi, Naofumi

    2006-01-01

    Objective: To assess the CT and magnetic resonance (MR) imaging findings of thymic epithelial tumors classified according to the current World Health Organization (WHO) histologic classification and to determine useful findings in differentiating the main subtypes. Materials and methods: Sixty patients with thymic epithelial tumor who underwent both CT and MR imaging were reviewed retrospectively. All cases were classified according to the 2004 WHO classification. The following findings were assessed in each case on both CT and MRI: size of tumor, contour, perimeter of capsule; homogeneity, presence of septum, hemorrhage, necrotic or cystic component within tumor; presence of mediastinal lymphadenopathy, pleural effusion, and great vessel invasion. These imaging characteristics of 30 low-risk thymomas (4 type A, 12 type AB, and 14 type B1), 18 high-risk thymomas (11 type B2 and seven type B3), and 12 thymic carcinomas on CT and MR imaging were compared using the chi-square test. Comparison between CT and MR findings was performed by using McNemar test. Results: On both CT and MR imaging, thymic carcinomas were more likely to have irregular contours (P < .001), necrotic or cystic component (P < .05), heterogeneous contrast-enhancement (P < .05), lymphadenopathy (P < .0001), and great vessel invasion (P < .001) than low-risk and high-risk thymomas. On MR imaging, the findings of almost complete capsule, septum, and homogenous enhancement were more commonly seen in low-risk thymomas than high-risk thymomas and thymic carcinomas (P < .05). MR imaging was superior to CT in the depiction of capsule, septum, or hemorrhage within tumor (all comparison, P < .05). Conclusion: The presence of irregular contour, necrotic or cystic component, heterogeneous enhancement, lymphadenopathy, and great vessel invasion on CT or MR imaging are strongly suggestive of thymic carcinomas. On MR imaging, the findings of contour, capsule, septum, and homogenous enhancement are helpful in

  10. Escaping carbon lock-in

    International Nuclear Information System (INIS)

    Unruh, G.C.

    2002-01-01

    This article explores the climate policy implications of the arguments made in ''Understanding carbon lock-in'' (Unruh, 2000), which posited that industrial countries have become locked-into fossil fuel-based energy systems through path dependent processes driven by increasing returns to scale. Carbon lock-in arises through technological, organizational, social and institutional co-evolution, ''culminating'' in what was termed as techno-institutional complex (TIC). In order to resolve the climate problem, an escape from the lock-in condition is required. However, due to the self-referential nature of TIC, escape conditions are unlikely to be generated internally and it is argued here that erogenous forces are probably required. (author)

  11. Growth hormone in the presence of laminin modulates interaction of human thymic epithelial cells and thymocytes in vitro

    Directory of Open Access Journals (Sweden)

    Marvin Paulo Lins

    Full Text Available BACKGROUND: Several evidences indicate that hormones and neuropeptides function as immunomodulators. Among these, growth hormone (GH is known to act on the thymic microenvironment, supporting its role in thymocyte differentiation. The aim of this study was to evaluate the effect of GH on human thymocytes and thymic epithelial cells (TEC in the presence of laminin. RESULTS: GH increased thymocyte adhesion on BSA-coated and further on laminin-coated surfaces. The number of migrating cells in laminin-coated membrane was higher in GH-treated thymocyte group. In both results, VLA-6 expression on thymocytes was constant. Also, treatment with GH enhanced laminin production by TEC after 24 h in culture. However, VLA-6 integrin expression on TEC remained unchanged. Finally, TEC/thymocyte co-culture model demonstrated that GH elevated absolute number of double-negative (CD4-CD8- and single-positive CD4+ and CD8+ thymocytes. A decrease in cell number was noted in double-positive (CD4+CD8+ thymocytes. CONCLUSIONS: The results of this study demonstrate that GH is capable of enhancing the migratory capacity of human thymocytes in the presence of laminin and promotes modulation of thymocyte subsets after co-culture with TEC.

  12. Intrapericardial primary thymic carcinoma in a 73-year-old man.

    Science.gov (United States)

    Calderon, Ana Maria; Merchan, Juan Andres; Rozo, Juan Carlos; Guerrero, Cesar Ivan; Treistman, Bernardo; Sulak, Laura E; Cheong, Benjamin Y C; Rodríguez, German; Mesa, Andrés

    2008-01-01

    Thymic carcinoma is a rare, highly aggressive type of tumor that typically occurs in the anterior mediastinum. We describe the case of a 73-year-old man who presented with weakness, cough, dyspnea, anorexia, and weight loss. An echocardiogram showed an intrapericardial mass that occupied the space around the lateral walls of the left ventricle and distally compressed the right ventricle. Magnetic resonance imaging and a biopsy confirmed the presence of intrapericardial primary thymic carcinoma. The patient underwent surgical excision of the tumor and died of right ventricular rupture during the procedure. This case highlights the importance of considering thymic carcinoma whenever an otherwise unexplained intrapericardial mass is encountered.

  13. EscapED: A Framework for Creating Educational Escape Rooms and Interactive Games to For Higher/Further Education.

    Directory of Open Access Journals (Sweden)

    Samantha Jane Clarke

    2017-09-01

    Full Text Available Game-based learning (GBL is often found to be technologically driven and more often than not, serious games for instance, are conceptualised and designed solely for digital platforms and state of the art technologies. To encourage a greater discussion on the potential benefits and challenges of a more holistic approach to developing GBL that promote human centered interactions and play for learning, the authors present the escapED programme. The escapED programme was conceived following the recent entertainment trend of escape rooms and is used for developing non-digital GBL approaches within education. escapED aids the design and creation of educational Escape Rooms and Interactive Gaming Experiences for staff and students in further/higher education settings. The paper first presents a pilot study that was used to assess the feasibility and acceptance of University teaching staff of embedding interactive GBL into a higher education environment. The authors then present the escapED theoretical framework that was used to create the prototype game for the pilot study as a tool to aid future design and development of on-site interactive experiences. The paper also presents an external developer report of using the escapED framework to develop a prototype game for teaching research methods to Southampton University students. Finally, the authors present a discussion on the use of the escapED framework so far and plans for future work and evaluation in order to provide engaging alternatives for learning and soft skills development amongst higher education staff andstudents.

  14. T-lymphocyte subsets, thymic size and breastfeeding in infancy

    DEFF Research Database (Denmark)

    Jeppesen, Dorthe Lisbeth; Hasselbalch, Helle; Lisse, Ida M

    2004-01-01

    We followed the changes in concentration of T-lymphocyte subsets (CD4+ and CD8+ cells) in peripheral blood and thymus size during infancy. Previous studies have found increased thymus size in breastfed infants. The present study analyzed the association between breastfeeding and the number of CD4......+ and CD8+ cells. Two different populations of infants between birth and 1 year of age were examined. Study Group I: infants with a variable duration of breastfeeding. Study Group II: long-term breastfed infants. In both groups a correlation was found between CD8+ cells and the thymic index at 10 months...... to 10 months of age; and a positive correlation between the number of breastfeedings per day at 8 months of age, and an increase in CD4+ cells from 8 to 10 months of age (p Breastfeeding might have both a current and long...

  15. The diagnosis of thymoma and thymic atrophy in patients with myasthenia gravis

    International Nuclear Information System (INIS)

    Sund, K.K.; Skeie, G.O.; Gilhus, N.E.; Aarli, J.A.; Varhaug, J.E.

    1997-01-01

    The authors have compared clinical, immunological and radiological data in 20 patients with myasthenia gravis and thymoma and in 21 patients with myasthenia gravis and thymic atrophy. The median age at onset was 54 years in the thymoma group and 63 years in the thymic atrophy group. The severity of the disease was similar in the two groups, and there was no significant difference in the concentration of acetylcholine receptor antibodies. CA antibodies were demonstrated in 17/20 thymoma patients and in 6/21 with thymic atrophy, while 19/20 thymoma patients had antibodies to titin, compared with 9/21 among those with thymic atrophy. The diagnosis and treatment of patients with myasthenia gravis is based upon an evaluation of clinical, immunological and radiological data. 28 refs., 2 tabs

  16. Production of BMP4 by endothelial cells is crucial for endogenous thymic regeneration

    Science.gov (United States)

    Wertheimer, Tobias; Velardi, Enrico; Tsai, Jennifer; Cooper, Kirsten; Xiao, Shiyun; Kloss, Christopher C.; Ottmüller, Katja J.; Mokhtari, Zeinab; Brede, Christian; deRoos, Paul; Kinsella, Sinéad; Palikuqi, Brisa; Ginsberg, Michael; Young, Lauren F.; Kreines, Fabiana; Lieberman, Sophia R.; Lazrak, Amina; Guo, Peipei; Malard, Florent; Smith, Odette M.; Shono, Yusuke; Jenq, Robert R.; Hanash, Alan M.; Nolan, Daniel J.; Butler, Jason M.; Beilhack, Andreas; Manley, Nancy R.; Rafii, Shahin; Dudakov, Jarrod A; van den Brink, Marcel RM

    2018-01-01

    The thymus is extremely sensitive to damage but also has a remarkable ability to repair itself. However, the mechanisms underlying this endogenous regeneration remain poorly understood and this capacity diminishes considerably with age. Here we show that thymic endothelial cells (ECs) comprise a critical pathway of regeneration, via their production of BMP4. ECs increased their production of BMP4 after thymic damage, and abrogating BMP4 signalling or production by either pharmacologic or genetic inhibition impaired thymic repair. EC-derived BMP4 acted on thymic epithelial cells (TECs) to increase their expression of Foxn1, a key transcription factor involved in TEC development, maintenance and regeneration; and its downstream targets such as Dll4, itself a key mediator of thymocyte development and regeneration. These studies demonstrate the importance of the BMP4 pathway in endogenous tissue regeneration and offer a potential clinical approach to enhance T cell immunity. PMID:29330161

  17. Implantation of cultured thymic fragments in patients with acquired immunodeficiency syndrome

    NARCIS (Netherlands)

    Danner, S. A.; Schuurman, H. J.; Lange, J. M.; Gmelig Meyling, F. H.; Schellekens, P. T.; Huber, J.; Kater, L.

    1986-01-01

    Cultured thymic fragments were implanted in one patient with acquired immunodeficiency syndrome (AIDS)-related complex (ARC) and in eight AIDS patients with opportunistic infections (OIs, four patients), Kaposi's sarcoma (KS, two patients), or both (two patients). Thereafter, objective clinical

  18. A rear case of multilocular thymic cyst with follicular lymphoid hyperplasia; Radiologic and histopathologic features

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Suk; Cha, Eun Jung [Konyang University Hospital, Daejeon (Korea, Republic of)

    2016-06-15

    Multilocular thymic cysts are rare and acquired lesions induced by an inflammatory arising within the thymus. We report a rare case of multilocular thymic cyst with follicular lymphoid hyperplasia in a 59-year-old female. Chest CT and MRI revealed a large multilocular cystic mass, which contains thick septa and nodules in the thymus. F-18 FDG PET/CT showed almost no FDG uptake of the multilocular cystic mass but moderate FDG uptake of the solid nodules. Extended total thymectomy was performed. Histopathological findings revealed follicular lymphoid hyperplasia of thymic tissue but no neoplastic lesion. Based on these findings, diagnosis of multilocular thymic cyst with follicular lymphoid hyperplasia was made. This is a rare case that preoperatively was difficult to diagnose.

  19. Genetic analysis of radiation-induced mouse thymic lymphomas

    International Nuclear Information System (INIS)

    Kominami, R.; Wakabayashi, Y.; Niwa, O.

    2003-01-01

    Mouse thymic lymphomas are one of the classic models of radiation-induced malignancies, and the model has been used for the study of genes involved in carcinogenesis. ras oncogenes are the first isolate which undergoes mutations in 10 to 30 % of lymphomas, and p16INK4a and p19ARF in the INK4a-ARF locus are also frequently inactivated. In our previous study, the inactivation of Ikaros, a key regurator of lymphoid system, was found in those lymphomas, and it was suggested that there are other responsible genes yet to be discovered. On the other hand, genetic predisposition to radiation-induced lymphoma often differs in different strains, and this reflects the presence of low penetrance genes that can modify the impact of a given mutation. Little study of such modifiers or susceptibility genes has been performed, either. Recent availability of databases on mouse genome information and the power of mouse genetic system underline usefulness of the lymphoma model in search for novel genes involved, which may provide clues to molecular mechanisms of development of the radiogenic lymphoma and also genes involved in human lymphomas and other malignancies. Accordingly, we have carried out positional cloning for the two different types of tumor-related genes. In this symposium, our current progress is presented that includes genetic mapping of susceptibility/ resistance loci on mouse chromosomes 4, 5 and 19, and also functional analysis of a novel tumor suppressor gene, Rit1/Bcl11b, that has been isolated from allelic loss (LOH) mapping and sequence analysis for γ -ray induced mouse thymic lymphomas

  20. Radiation-induced quantitative alterations in prenatal thymic development in the beagle dog

    International Nuclear Information System (INIS)

    Miller, G.K.; Benjamin, S.A.

    1985-01-01

    Quantitative morphology of the canine fetal thymus was studied to evaluate the age-dependent radiosensitivity of the developing immune system. Pregnant beagle dams received abdominal 60 Co gamma exposures (200 R) or were sham irradiated at one of three ages in gestation, 30, 40, or 45 days. The mean calculated dose to each fetus was 1.5 Gray. One-half of the fetuses in each litter were harvested by hysterotomy at 5 days and one-half at 10 days post-irradiation (PI). The volumes of the thymic lobules and lobular cortices were significantly reduced at 5 and 10 days PI when compared with age-matched controls. Thymic cortical volumes in irradiated fetuses were reduced between 13 and 29% from control volumes by 5 days PI and 8 and 13% by 10 day PI. Thymic medullary volumes in irradiated fetuses were reduced 18 to 23% by 5 days PI and 27 to 54% by 10 days PI. The reductions in medullary volumes in fetuses irradiated at 35, 40, and 45 days of gestation and evaluated at 10 days PI were 54, 38, and 27%, respectively. Although injury to both thymic cortices and medullas was greater following exposures earlier in gestation, damage to medullas was relatively more severe than in cortices following exposure at any one age. The degree of reduction of medullary volume reflects thymic epithelial injury and is surprising since thymic epithelium is considered to be radioresistant in the adult. Such injury may have serious consequences postnatally as normal differentiation of T cell subpopulations is dependent upon the integrity of the thymic microenvironment. Damage to the thymic microenvironment could result in defects in immunologic regulation and in immune deficiencies

  1. Optimal surgical approach to thymic malignancies: New trends challenging old dogmas.

    Science.gov (United States)

    Ruffini, Enrico; Filosso, Pier Luigi; Guerrera, Francesco; Lausi, Paolo; Lyberis, Paraskevas; Oliaro, Alberto

    2018-04-01

    Until recently, the surgical approach to thymic tumors has remained basically unchanged. The collaborative effort led by ITMIG with the collaboration of regional and society-based interest groups (ESTS, JART) produced an enthusiastic surge of interest in testing the new technological advances in thoracic surgery and many historical dogmas in thymic surgery have been questioned and challenged. The present review addresses the new trends in the optimal surgical management of thymic tumors based on the review of the current literature. 1. Minimally-invasive techniques (MIT) including video-assisted thoracic surgery (VATS) and robotic-assisted thoracic Surgery (RATS) are now to be considered the standard of care in early-stage thymic tumors. MIT are no inferior to open approaches in terms of postoperative complications, loco-regional recurrence rates and survival. MIT are associated with a shorter length of stay, reduced intraoperative blood loss and better cosmetic results. 2. The adoption of the ITMIG/IASLC TNM staging system for thymic tumors requires a paradigm shift among thoracic surgeons to include regional lymphadenectomy according to the IASLC/ITMIG nodal map in the surgical management of thymic tumors. 3. A limited thymectomy instead of total thymectomy along with the removal of the thymic tumor in nonmyasthenic Stage I-II tumors has been proposed by some authors, although the results are not uniform. Until more mature data is available, adherence to the current guidelines recommending total thymectomy in addition to thymomectomy is always indicated. 4. In locally-advanced Stage IVa patients with pleural involvement, major pleural resections, including pleurectomy/decortication or extrapleural pneumonectomy are indicated, provided a complete resection of the pleural deposits is anticipated, usually in a multidisciplinary setting, with excellent long-term results. The incorporation of these new concepts and techniques in the surgical armamentarium of the

  2. Effect of allogenic thymic cells on radioleukaemogenesis in AKR-T1ALD mice

    International Nuclear Information System (INIS)

    Legrand, E.; Sankar-Mistry, P.; Kressmann, M.C.

    1975-01-01

    When AKR mice are irradiated with a sub-lethal dose (4 times 175 R), thymic lymphosarcomas (L.S.) occur earlier than in controls. This accelerated leukaemogenesis is not inhibited by syngenic restoration with bone marrows cells (BM). Using the AKR/T1ALD substrain which bears 38 chromosomes with 1 metacentric markers, it has been shown that AKR radio-chimaeras restored by T1ALD BM developed two kinds of L.S.: early (radiation-induced) L.S. originating mainly from host cells surviving irradiation and late L.S. from donor cells. The experiments were to investigate the potential influence of normal allogenic thymic cells, with or without syngenic B.M., on the incidence, latency and origin of LS appearing in irradiated AKR recipients. Adding C3H allogenic thymic cells to syngenic B.M. increases the percentage of early L.S. whose latencies are unchanged. Besides, when C3H thymic cells are injected to irradiated controls without syngenic B.M. cells, L.S. are seen to occur significantly earlier than in just the irradiated animals alone. In radio-chimaeras restored by allogenic thymic cells and syngenic B.M., except in one case, all the L.S. were seen to originate from B.M. cells. The interpretation of these results depends on the possible role of allogenic thymic cells on host cells surviving the irradiation, or the exogeneous B.M. In the first case, allogenic thymocytes could induce a graft versus host reaction increasing the post-irradiation depletion of lymphoid system and hastening thymic endoregeneration which is supposed to be the first step towards leukaemogenesis. The second hypothesis, which seems the most likely, would be that C1H thymic cells could selectively act on host cells surviving irradiation and enhance the differenciation of haemopoietic precursors at the expense of the lymphoid cells [fr

  3. Malaria parasites: the great escape

    Directory of Open Access Journals (Sweden)

    Laurent Rénia

    2016-11-01

    Full Text Available Parasites of the genus Plasmodium have a complex life cycle. They alternate between their final mosquito host and their intermediate hosts. The parasite can be either extra- or intracellular, depending on the stage of development. By modifying their shape, motility, and metabolic requirements, the parasite adapts to the different environments in their different hosts. The parasite has evolved to escape the multiple immune mechanisms in the host that try to block parasite development at the different stages of their development. In this article, we describe the mechanisms reported thus far that allow the Plasmodium parasite to evade innate and adaptive immune responses.

  4. Thymic B cell development is controlled by the B potential of progenitors via both hematopoietic-intrinsic and thymic microenvironment-intrinsic regulatory mechanisms.

    Directory of Open Access Journals (Sweden)

    Shiyun Xiao

    Full Text Available Hematopoietic stem cells (HSCs derived from birth through adult possess differing differentiation potential for T or B cell fate in the thymus; neonatal bone marrow (BM cells also have a higher potential for B cell production in BM compared to adult HSCs. We hypothesized that this hematopoietic-intrinsic B potential might also regulate B cell development in the thymus during ontogeny.Foxn1lacZ mutant mice are a model in which down regulation of a thymic epithelial cell (TEC specific transcription factor beginning one week postnatal causes a dramatic reduction of thymocytes production. In this study, we found that while T cells were decreased, the frequency of thymic B cells was greatly increased in these mutants in the perinatal period. We used this model to characterize the mechanisms in the thymus controlling B cell development.Foxn1lacZ mutants, T cell committed intrathymic progenitors (DN1a,b were progressively reduced beginning one week after birth, while thymic B cells peaked at 3-4 weeks with pre-B-II progenitor phenotype, and originated in the thymus. Heterochronic chimeras showed that the capacity for thymic B cell production was due to a combination of higher B potential of neonatal HSCs, combined with a thymic microenvironment deficiency including reduction of DL4 and increase of IL-7 that promoted B cell fate.Our findings indicate that the capacity and time course for thymic B-cell production are primarily controlled by the hematopoietic-intrinsic potential for B cells themselves during ontogeny, but that signals from TECs microenvironment also influence the frequency and differentiation potential of B cell development in the thymus.

  5. CT features of the subtypes of thymic epithelial tumors on the basis of the world health organization classification

    International Nuclear Information System (INIS)

    Guo Xiaoyu; Yu Hong; Xiao Xiangsheng

    2013-01-01

    Thymic epithelial tumors including thymomas and thymic carcinomas have well-known heterogeneous oncologic behaviors and variable histologic features. They show variable and unpredictable evolutions ranging from an indolent non-invasive feature to a highly infiltrative and metastasising one. Currently, CT is a common and efficient imaging method for assessing thymic epithelial tumors. CT evaluation is the main reference for preoperative clinic staging and histological classification. CT features of subtypes of thymic epithelial tumors on the basis of the World Health Organization classification provide the foundation for the diagnosis and predicting prognosis. (authors)

  6. Radiotherapy for invasive thymoma and thymic carcinoma. Clinicopathological review

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, R.; Stuecklschweiger, G.F.; Prettenhofer, U.; Stranzl, H.; Hackl, A. [Univ. Graz (Austria). Dept. of Radiotherapy; Beham-Schmid, C. [Univ. Graz (Austria). Dept. of Pathology; Groell, R. [Univ. Graz (Austria). Dept. of Radiology; Smolle-Juettner, F.M.; Renner, H. [Univ. Graz (Austria). Dept. of Thoracic and Hyperbaric Surgery; Quehenberger, F. [Univ. Graz (Austria). Dept. of Medical Informatics, Statistics and Documentation

    1999-06-01

    All 33 patients were irradiated with a mean dose of 50 Gy after complete resection (16 patients), partial resection (9 patients) of biopsy (8 patients). Staging was done according to the Masaoka classification; there were 12 Stage II, 12 Stage III and 9 Stage IV patients. Results: In patients with invasive thymoma Stage II to IV (median follow-up 54.4 months) Kaplan-Meier estimates of overall survival (OS), disease-specific (DSS) and disease-free survival (DFS) at 5 years were 63.7% (95% confidence interval [CI], 42 to 84%), 88.3% (CI, 75 to 100%) and 77,4% (CI, 58 to 95%), respectively. Among the prognostic factors tested, such as age, myasthenia gravis, completeness of surgery and histologic subclassification, total radiation dose, and Masaoka Stage, the latter was the only significant predictor of improved survival (p=0.04). Considering local control, radiation dose was a significant prognostic factor (p=0.0006). In patients with thymic carcinoma (median follow-up 43.4 months) 5 year DSS, and DFS were 22.2% (CI, 0 to 60%) and 16.7% (CI, 0 to 46%), respectively. Thymoma as compared to thymic carcinoma had a statistically significant better DSS (p=0.007) and DFS (p=0.0007). Conclusion: Postoperative radiotherapy with sufficient doses plays an important role as adjuvant treatment in complete or incomplete resected invasive Stage II to III thymoma. In unresectable thymoma Stage III to IV as well as in thymic carcinoma a multimodality approach should be considered to improve survival. (orig.) [Deutsch] Alle 33 Patienten wurden nach kompletter Resektion (n=16), Teilresektion (n=9) oder Biopsie (n=8) mit einer mittleren Dosis von 50 Gy (30 bis 60 Gy) bestrahlt. Die Stadieneinteilung nach Masaoka ergab jeweils zwoelf Patienten in Stadium II und III sowie neun Patienten im Stadium IV. Ergebnisse: Patienten mit einem invasivem Thymom Masaoka-Stadium II bis IV (mediane Nachsorgezeit 54,4 Monate) hatten ein Fuenf-Jahres-Gesamtueberleben, krankheitsspezifisches und

  7. Anomalous barrier escape: The roles of noise distribution and correlation

    Science.gov (United States)

    Hu, Meng; Zhang, Jia-Ming; Bao, Jing-Dong

    2017-05-01

    We study numerically and analytically the barrier escape dynamics of a particle driven by an underlying correlated Lévy noise for a smooth metastable potential. A "quasi-monochrome-color" Lévy noise, i.e., the first-order derivative variable of a linear second-order differential equation subjected to a symmetric α-stable white Lévy noise, also called the harmonic velocity Lévy noise, is proposed. Note that the time-integral of the noise Green function of this kind is equal to zero. This leads to the existence of underlying negative time correlation and implies that a step in one direction is likely followed by a step in the other direction. By using the noise of this kind as a driving source, we discuss the competition between long flights and underlying negative correlations in the metastable dynamics. The quite rich behaviors in the parameter space including an optimum α for the stationary escape rate have been found. Remarkably, slow diffusion does not decrease the stationary rate while a negative correlation increases net escape. An approximate expression for the Lévy-Kramers rate is obtained to support the numerically observed dependencies.

  8. Adjuvant Therapy for Thymic Carcinoma--A Decade of Experience in a Taiwan National Teaching Hospital.

    Directory of Open Access Journals (Sweden)

    Yen-Han Tseng

    Full Text Available Thymic carcinomas are rare tumors for which surgical resection is the first treatment of choice. The role of adjuvant treatment after surgery is unknown because of limited available data. The present study evaluated the efficacy of post-surgery adjuvant chemotherapy or radiotherapy in patients with thymic carcinoma.To evaluate the role of adjuvant therapy in patients with thymic carcinoma, we retrospectively reviewed the records of patients with thymic carcinoma who were diagnosed and treated between 2004 and 2014.Among 78 patients with thymic carcinoma, 30 patients received surgical resection. Progression-free survival (PFS and overall survival (OS were significantly longer among these patients than among patients who received other treatments (PFS: 88.4 months vs 9.1 months, p<0.001; OS: 134.9 months vs 60.9 months; p = 0.003. Patients with stage III thymic carcinoma who received surgery had a longer OS than patients who did not receive surgery (70.1 months vs 23.9 months; p = 0.017, n = 11. Among 47 patients with stage IV carcinoma, 12 patients who received an extended thymothymectomy had a longer PFS than 35 patients who did not receive surgery (18.9 months vs 8.7 months; p = 0.029. Among 30 patients (with stage I- IV carcinoma who received primary lesion surgery, 19 patients received an R0 resection and 9 patients of the 19 patients received adjuvant radiotherapy. These patients had longer PFS (50.3 months than 2 patients who received adjuvant chemotherapy (5.9 months or 4 patients who received concurrent chemoradiotherapy (7.5 months after surgery (p = 0.003.Surgical resection should be considered for patients with thymic carcinoma, even for patients with locally advanced or stage IV carcinoma. Adjuvant radiotherapy resulted in a better PFS after R0 resection.

  9. Lymphocyte depletion in thymic nurse cells: a tool to identify in situ lympho-epithelial complexes having thymic nurse cell characteristics

    NARCIS (Netherlands)

    Leene, W.; de Waal Malefijt, R.; Roholl, P. J.; Hoeben, K. A.

    1988-01-01

    In situ pre-existing complexes of epithelial cells and thymocytes having thymic nurse cell characteristics were visualized in the murine thymus cortex using dexamethasone as a potent killer of cortisone-sensitive thymocytes. The degradation and subsequent depletion of cortisone-sensitive thymocytes

  10. Polyhexamethyleneguanidine phosphate induces severe lung inflammation, fibrosis, and thymic atrophy.

    Science.gov (United States)

    Song, Jeong Ah; Park, Hyun-Ju; Yang, Mi-Jin; Jung, Kyung Jin; Yang, Hyo-Seon; Song, Chang-Woo; Lee, Kyuhong

    2014-07-01

    Polyhexamethyleneguanidine phosphate (PHMG-P) has been widely used as a disinfectant because of its strong bactericidal activity and low toxicity. However, in 2011, the Korea Centers for Disease Control and Prevention and the Ministry of Health and Welfare reported that a suspicious outbreak of pulmonary disease might have originated from humidifier disinfectants. The purpose of this study was to assess the toxicity of PHMG-P following direct exposure to the lung. PHMG-P (0.3, 0.9, or 1.5 mg/kg) was instilled into the lungs of mice. The levels of proinflammatory markers and fibrotic markers were quantified in lung tissues and flow cytometry was used to evaluate T cell distribution in the thymus. Administration of PHMG-P induced proinflammatory cytokines elevation and infiltration of immune cells into the lungs. Histopathological analysis revealed a dose-dependent exacerbation of both inflammation and pulmonary fibrosis on day 14. PHMG-P also decreased the total cell number and the CD4(+)/CD8(+) cell ratio in the thymus, with the histopathological examination indicating severe reduction of cortex and medulla. The mRNA levels of biomarkers associated with T cell development also decreased markedly. These findings suggest that exposure of lung tissue to PHMG-P leads to pulmonary inflammation and fibrosis as well as thymic atrophy. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Appearance of thymic nurse cells after gamma irradiation

    International Nuclear Information System (INIS)

    Mulder, A.H.; Bekkum, D.W. van

    1983-01-01

    Since prothymocytes home from the bone marrow to the thymus, it was tested in the mouse whether prothymocytes could be recaptured from thymic nurse cells (TNC). Bone marrow cells were labelled with the red fluorescing anthracycline daunomycin and varying numbers (up to 25 x 10 6 nucleated bone marrow cells) were injected into lethally irradiated recipients. At several time intervals after transplantation (up to 24 hours), thymuses were removed and the TNCs were isolated. No specific red fluorescence was found within the TNCs. These experiments were repeated with supravital compounds at concentrations which have been shown not to affect viability, homing pattern and function. Again, no specific fluoresence was found in the TNC after transplantation of labelled bone marrow into irradiated mice. The relationship between the dose of total body gamma irradiation and the time after irradiation was investigated. Maximal numbers of TNCs were found at 6 hours after irradiation with 4 Gy. Eight to 12 hours after irradiation, the number of TNCs isolated decreased and had returned to preirradiation levels at 24 hours. The relation between TBI dose and the number of TNCs per thymus is shown. The number determined at 3 hours increased with the dose to reach a maximum at 4 Gy. The authors later studied the morphology of the TNCs isolated at 4 to 6 hours after irradiation. On electron microscopic examination, signs of degeneration and death of the enclosed thymocytes was detected. (Auth.)

  12. Therapeutic implications of thymic uptake of radioiodine in thyroid carcinoma

    International Nuclear Information System (INIS)

    Wilson, L.M.; Barrington, S.F.; Kettle, A.G.; O'Doherty, M.J.; Coakley, A.J.; Morrison, I.D.

    1998-01-01

    The management of 38 consecutive patients with differentiated thyroid carcinoma in the period 1991-1996, who each received at least one therapy dose of iodine-131, was reviewed, looking in particular at those in whom anterior mediastinal uptake was demonstrated on scans taken 3 and 7 days post-therapy. Such activity was noted in ten patients. On the basis of clinical follow-up, thyroglobulin measurement and radiological and other scintigraphic imaging, in nine of the ten patients the anterior mediastinal activity was attributed to physiological thymic uptake. Of those nine, all were under 50 years of age; seven were considered disease free, one had residual disease in the neck and one had distant metastases. Physiological uptake by the thymus was more prominent on the 7-day scans and in patients with low tumour volumes. For appropriate patient management it is essential to recognise that physiological uptake of 131 I by the thymus in patients under 50 years of age is a potential cause of false-positive therapy scans. (orig.)

  13. Preoperative CT prediction for Masaoka staging of thymic epithelial tumor

    International Nuclear Information System (INIS)

    Feng Zhan; Huang Zhen; Zhang Liang

    2013-01-01

    Objective: To discuss the value of CT prognosis on the Masaoka staging system of thymic epithelial tumors (TET) before surgical resection. Methods: The CT images of 102 patients with TET proved by surgery and pathology were reviewed retrospectively. The TET were reclassified according to Masaoka stage system. The size, homogeneity, sharp, contour, infiltration of surrounding tissue, and metastasis on CT were analyzed with Logistic analysis. The diagnostic value was also evaluated with a ROC curve. Results: Masaoka pathologic stages were stage Ⅰ for 36 (35.3 %), stage Ⅱ for 27 (26.5 %), stage Ⅲ for 30 (29.4 %), and stage Ⅳ for 9 (8.8 %). A multivariable Logistic regression model showed that TET with larger size of tumor (20/35, P = 0.0371, OR = 4.539), irregular or lobulated tumor contour (26/42, P = 0.0230, OR = 4.870), heterogeneous (21/33, P = 0.0154, OR = 6.020), infiltration of surrounding fat (25/32, P = 0.0019, OR = 14.005), and pleural seeding (11/11, P = 0.0032, OR = 36.153) were more likely to have stage Ⅲ or Ⅳ disease. The area under ROC curve was 0.940. Conclusions: The tumor CT imaging features can differentiate between stage Ⅰ, Ⅱ and stage Ⅲ, Ⅳ disease. This helps identified patients more likely to benefit from neoadjuvant therapy. (authors)

  14. Signal transduction around thymic stromal lymphopoietin (TSLP in atopic asthma

    Directory of Open Access Journals (Sweden)

    Kuepper Michael

    2008-08-01

    Full Text Available Abstract Thymic stromal lymphopoietin (TSLP, a novel interleukin-7-like cytokine, triggers dendritic cell-mediated inflammatory responses ultimately executed by T helper cells of the Th2 subtype. TSLP emerged as a central player in the development of allergic symptoms, especially in the airways, and is a prime regulatory cytokine at the interface of virus- or antigen-exposed epithelial cells and dendritic cells (DCs. DCs activated by epithelium-derived TSLP can promote naïve CD4+ T cells to adopt a Th2 phenotype, which in turn recruite eosinophilic and basophilic granulocytes as well as mast cells into the airway mucosa. These different cells secrete inflammatory cytokines and chemokines operative in inducing an allergic inflammation and atopic asthma. TSLP is, thus, involved in the control of both an innate and an adaptive immune response. Since TSLP links contact of allergen with the airway epithelium to the onset and maintainance of the asthmatic syndrome, defining the signal transduction underlying TSLP expression and function is of profound interest for a better understandimg of the disease and for the development of new therapeutics.

  15. Two examples of escaping harmonic maps

    International Nuclear Information System (INIS)

    Pereira do Valle, A.; Verjovsky, A.

    1988-12-01

    This paper is part of a study on the existence of special harmonic maps on complete non-compact Riemannian manifolds. We generalize the notion of escaping geodesic and prove some results on the existence of escaping harmonic maps. 11 refs, 6 figs

  16. Ectopic Thymic Cyst of the Subglottis: Considerations for Diagnosis and Management.

    Science.gov (United States)

    Ahmad, Iram; Kirby, Patricia; Liming, Bryan

    2018-03-01

    To share the diagnostic and management challenges created by an extremely rare airway lesion-the subglottic ectopic thymic cyst. Case report and literature review. We review the presentation, management, and clinical course of an infant who presented with a subglottic mass that was histologically confirmed as a thymic cyst. A brief literature review supplements the case presentation Results: We present the third described case of an ectopic thymic cyst presenting as a subglottic mass. The differential diagnosis of subglottic masses in neonates consists primarily of subglottic hemangioma and mucous retention cysts. Otolaryngologists must be prepared for unexpected findings when dealing with critical airways. We compare the presentation and management of our patient with the 2 previously described cases. We propose an embryologic theory for the origin of these rare lesions. An ectopic thymic cyst is a rare and unexpected cause of neonatal stridor. Management of pediatric airway lesions must allow for unexpected findings at the time of diagnostic and therapeutic endoscopy. The appropriate management of subglottic thymic cysts is poorly defined, but close surveillance for recurrence is mandatory.

  17. Utility of Electrocardiography (ECG)-Gated Computed Tomography (CT) for Preoperative Evaluations of Thymic Epithelial Tumors.

    Science.gov (United States)

    Ozawa, Yoshiyuki; Hara, Masaki; Nakagawa, Motoo; Shibamoto, Yuta

    2016-01-01

    Preoperative evaluation of invasion to the adjacent organs is important for the thymic epithelial tumors on CT. The purpose of our study was to evaluate the utility of electrocardiography (ECG)-gated CT for assessing thymic epithelial tumors with regard to the motion artifacts produced and the preoperative diagnostic accuracy of the technique. Forty thymic epithelial tumors (36 thymomas and 4 thymic carcinomas) were examined with ECG-gated contrast-enhanced CT using a dual source scanner. The scan delay after the contrast media injection was 30 s for the non-ECG-gated CT and 100 s for the ECG-gated CT. Two radiologists blindly evaluated both the non-ECG-gated and ECG-gated CT images for motion artifacts and determined whether the tumors had invaded adjacent structures (mediastinal fat, superior vena cava, brachiocephalic veins, aorta, pulmonary artery, pericardium, or lungs) on each image. Motion artifacts were evaluated using a 3-grade scale. Surgical and pathological findings were used as a reference standard for tumor invasion. Motion artifacts were significantly reduced for all structures by ECG gating ( p =0.0089 for the lungs and p ECG-gated CT and ECG-gated CT demonstrated 79% and 95% accuracy, respectively, during assessments of pericardial invasion ( p =0.03). ECG-gated CT reduced the severity of motion artifacts and might be useful for preoperative assessment whether thymic epithelial tumors have invaded adjacent structures.

  18. Application values of 99mTc-methoxyisobutylisonitrile imaging for differentiating benign and malignant thymic masses.

    Science.gov (United States)

    Lu, Chenghui; Wang, Xufu; Liu, Bin; Liu, Xinfeng; Wang, Guoming; Zhang, Qin

    2017-08-01

    The aim of the present study was to investigate the application value of 99m Tc-methoxyisobutylisonitrile (MIBI) imaging to differentiate between benign and malignant thymic masses. A total of 32 patients with space-occupying mediastinal masses were enrolled and early and delayed-phase images were collected following injection with the imaging agent. The tumor to background ratio (T/N) values at the different phases were also recorded. The sensitivity of the qualitative analysis to distinguish between benign and malignant thymic masses was 95.24%, with specificity as 90.91%. The T/N values in the early and delayed phases were not significantly different in the group with benign thymic masses, but demonstrated statistical significant differences in the groups with low- and intermediate-grade malignant thymic masses. The T/N values at the above early and delayed phase were significantly different between the benign and low-grade malignancy groups, as well as between low- and moderate-grade malignancy groups. Those between the benign and moderate-grade malignancy groups demonstrated no significant difference. 99m Tc-MIBI imaging was able to differentiate between benign and malignant thymic masses, and the simultaneous semi-quantitative analysis of the T/N values of the tumors may be able to initially determine the degree of malignancy of thymoma.

  19. Acute respiratory failure revealing a multilocular thymic cyst in an infant: a case report.

    Science.gov (United States)

    Asma, Bouziri; Ammar, Khaldi; Khaled, Menif; Najoua, Guandoura; Nejla, Ben Jaballah

    2009-11-30

    Multilocular thymic cysts are rare benign lesions of the neck and mediastinum that can occur at any age. In children, multilocular thymic cysts are usually symptomatic after the age of 2 years and produce few symptoms. We present an unusual case of a multilocular thymic cyst diagnosed in a 3-month-old girl and causing severe respiratory failure. A 3 month-old-girl, with a medical history of dyspnea and wheezing since the age of 20 days, presented in our pediatric intensive care unit for acute respiratory failure requiring mechanical ventilation. The chest radiograph showed thoracic distension without any other abnormalities. The diagnosis of severe asthma was initially suspected and the patient was treated by intravenous corticosteroids and continuous perfusion of salbutamol without any improvement. A chest tomography scan was performed and demonstrated an anterior mediastinal multiseptated cystic mass extending from the inferior face of the thyroid gland to the left cardiophrenic angle. Sternotomy and excision biopsy were planned urgently. The cystic mass was excised completely. The histopathological examination confirmed the diagnosis of a multilocular thymic cyst. The particularities of our observation are the occurrence of a multilocular thymic cyst in a young infant and its presentation by a severe acute respiratory failure mimicking asthma.

  20. Platinum-based chemotherapy with or without thoracic radiation therapy in patients with unresectable thymic carcinoma

    International Nuclear Information System (INIS)

    Nakamura, Yoichi; Kunitoh, Hideo; Kubota, Kaoru

    2000-01-01

    Thymic carcinoma is a rare mediastinal neoplasm with poor prognosis. Although the clinical benefit of chemotherapy for thymic carcinoma is controversial, cisplatin-based chemotherapy with or without radiation therapy is ordinarily adopted in advanced cases. We evaluated the clinical outcome of platinum-based chemotherapy with or without radiation therapy in unresectable thymic carcinoma patients. Ten patients with unresectable thymic carcinoma were treated with platinum-based chemotherapy with or without radiation therapy in the National Cancer Center Hospital between 1989 and 1998. We reviewed the histological type, treatment, response and survival of these patients. Four of the 10 patients responded to chemotherapy and both the median progression-free survival period and the median response duration were 6.0 months. The median survival time was 11.0 months. There was no relationship between histological classification and prognosis. Platinum-based chemotherapy with or without thoracic radiation is, regardless of tumor histology, marginally effective in advanced thymic carcinoma patients, giving only a modest tumor response rate and short response duration and survival. (author)

  1. Escapism among players of MMORPGs--conceptual clarification, its relation to mental health factors, and development of a new measure.

    Science.gov (United States)

    Hagström, David; Kaldo, Viktor

    2014-01-01

    Previous studies show that the concept of escapism needs to be clarified and that its relation to problematic online gaming and other factors needs further examination. This study uses well-established, basic learning theory to clarify the concept of escapism, and examines its relation to problematic gaming, psychological distress, and satisfaction with life among players of massively multiplayer online role-playing games (MMORPGs). MMORPG players (n=201) answered an online questionnaire where these factors were measured and correlated with a previously developed scale on motivation to play (MTPI), including extra items to cover positive and negative aspects of escapism. Factor analysis and construct validation show that positive aspects of escapism are theoretically and empirically unstable and that escapism is best clarified as purely "negative escapism," corresponding to playing being negatively reinforced as a way of avoiding everyday hassles and distress. Negative escapism had a stronger relationship to symptoms of Internet addiction, psychological distress, and life satisfaction than other variables and other more positive motivations to play. Future studies should use the revised subscale for escapism (in the MTPI-R) presented in the present study, for example when screening for Internet addiction.

  2. Comparing Effective Treatments for Attention-Maintained and Escape- Maintained Behaviors in Children with Behavior Disorders: Brief Review and Analysis

    OpenAIRE

    Lauren Worcester; T. F. McLaughlin

    2013-01-01

    This literature review compares treatment for attention-maintainedversus escape maintained aberrant behavior in children with behavior disorders. Specifically, studies utilizing time out procedures, differential reinforcement procedures, noncontingent reinforcement, and functional communication training are discussed. It was found that these are effective treatments for attention-maintained behaviors; while escape extinction, positive and negative reinforcement, functional communication trai...

  3. Effect of Bcl11b genotypes and γ-radiation on the development of mouse thymic lymphomas

    International Nuclear Information System (INIS)

    Yoshikai, Yoshihiro; Sato, Toshihiro; Morita, Shinichi; Kohara, Yuki; Takagi, Ritsuo; Mishima, Yukio; Kominami, Ryo

    2008-01-01

    Bcl11b is a haploinsufficient tumor suppressor gene and expressed in many tissues such as thymus, brain and skin. Irradiated Bcl11b +/- heterozygous mice mostly develop thymic lymphomas, but the preference of Bcl11b inactivation for thymic lymphomas remains to be addressed. We produced Bcl11b +/- heterozygous and Bcl11b wild-type mice of p53 +/- background and compared their incidence of γ-ray induced thymic lymphomas. Majority of the tumors in p53 +/- mice were skin tumors, and only 5 (36%) of the 14 tumors were thymic lymphomas. In contrast, Bcl11b +/- p53 +/- doubly heterozygous mice developed thymic lymphomas at the frequency of 27 (79%) of the 34 tumors developed (P = 0.008). This indicates the preference of Bcl11b impairment for thymic lymphoma development. We also analyzed loss of the wild-type alleles in the 27 lymphomas, a predicted consequence given by γ-irradiation. However, the loss frequency was low, only six (22%) for Bcl11b and five (19%) for p53. The frequencies did not differ from those of spontaneously developed thymic lymphomas in the doubly heterozygous mice, though the latency of lymphoma development markedly differed between them. This suggests that the main contribution of irradiation at least in those mice is not for the tumor initiation by inducing allelic losses but probably for the promotion of thymic lymphoma development

  4. Modification of radiation-induced murine thymic lymphoma incidence by curcumin

    International Nuclear Information System (INIS)

    Dange, P.S.; Yadav, H.D.; Kumar, Vimalesh; Bhilwade, H.N.; Pandey, B.N.; Sarma, H.D.

    2017-01-01

    Curcumin is a known antioxidant, preventing radiation damage including carcinogenesis. However, concentration and feeding schedule of curcumin in modification of radiation induced thymic lymphoma incidence in vivo model has not been studied. We report here modification of incidence of γ-radiation-induced thymic lymphoma in mice fed with different doses of curcumin (0.05 to 1 %) in diet. Results: Female Swiss mice (6-8 weeks) fed with normal diet and exposed to 3 Gy whole body "6"0Co γ-irradiation (WBI) showed 85 % incidence of thymic lymphoma (TL) at 120 days post-irradiation. A concentration of 1 % curcumin was found the most effective in TL incidence prevention than other fed concentrations. The TL incidence was remarkably reduced when curcumin was fed to the mice before than after the radiation exposure. These results suggest modification of TL incidence by curcumin in irradiated mice involving DNA damage and apoptotic death mechanisms

  5. Alteration of T cell function in healthy persons with a history of thymic x irradiation

    International Nuclear Information System (INIS)

    Rieger, C.H.L.; Kraft, S.C.; Rothberg, R.M.

    1975-01-01

    The possible late effects of x irradiation to the infantile thymus were investigated by studying immune functions in 12 healthy persons with a history of thymic x irradiation and healthy control subjects. No differences were found in serum immunoglobulin values, humoral antibody levels, lymphocyte counts, and lymphocyte reactivity to phytohemagglutinin, vaccinia virus, purified protein derivative (PPD), and allogeneic cells. The irradiation group exhibited cellular hyperresponsiveness to streptokinase-streptodornase (SK-SD). In contrast, mean skin and in vitro lymphocyte responses to Candida albicans were depressed in the patients with thymic irradiation. A dissociation of these two Candida responses was found in only 1 of 14 healthy control subjects but in 7 of 12 irradiated individuals. While thymic irradiation did not result in impaired immunologic defenses leading to clinical disease, it caused alterations in T cell responses similar to those reported in patients with chronic mucocutaneous candidiasis

  6. Alteration of T cell function in healthy persons with a history of thymic x irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Rieger, C.H.L.; Kraft, S.C.; Rothberg, R.M.

    1975-10-01

    The possible late effects of x irradiation to the infantile thymus were investigated by studying immune functions in 12 healthy persons with a history of thymic x irradiation and healthy control subjects. No differences were found in serum immunoglobulin values, humoral antibody levels, lymphocyte counts, and lymphocyte reactivity to phytohemagglutinin, vaccinia virus, purified protein derivative (PPD), and allogeneic cells. The irradiation group exhibited cellular hyperresponsiveness to streptokinase-streptodornase (SK-SD). In contrast, mean skin and in vitro lymphocyte responses to Candida albicans were depressed in the patients with thymic irradiation. A dissociation of these two Candida responses was found in only 1 of 14 healthy control subjects but in 7 of 12 irradiated individuals. While thymic irradiation did not result in impaired immunologic defenses leading to clinical disease, it caused alterations in T cell responses similar to those reported in patients with chronic mucocutaneous candidiasis.

  7. Rapid development of thymic neuroendocrine carcinoma despite transcervical thymectomy in a patient with multiple endocrine neoplasia type 1

    Directory of Open Access Journals (Sweden)

    Dhalapathy Sadacharan

    2013-01-01

    Full Text Available Thymic neuroendocrine (NE tumors are a rare manifestation of multiple endocrine neoplasia syndrome type 1 (MEN-1. They are malignant and aggressive tumors and form a major cause of mortality in MEN-1. Transcervical thymectomy (TCT at the time of parathyroid surgery for primary hyperparathyroidism (PHPT in MEN-1 usually prevents thymic NE tumors. We report a 56-year-old nonsmoker male with sporadic MEN-1 who presented with thymic NE carcinoma developing rapidly within a span of 8 months after subtotal parathyroidectomy and TCT for PHPT. We present a brief review of literature on this rare NE malignancy, focusing on its occurrence despite TCT. This case highlights the fact that thymic NE carcinoma may develop even after TCT in MEN-1. Regular surveillance for these aggressive thymic NE tumors is mandatory even after TCT in MEN-1 setting.

  8. Phenotypic characterization of thymic prelymphoma cells of B10 mice treated with split-dose irradiation

    International Nuclear Information System (INIS)

    Muto, M.; Kubo, E.; Kamisaku, H.; Sado, T.

    1990-01-01

    Using an intrathymic injection assay on B10 Thy-1 congenic mice, it was demonstrated that thymic prelymphoma cells first developed within the thymuses from 4 to 8 days after split-dose irradiation and were detected in more than 63% of the test donor thymuses when examined at 21 and 31 days after irradiation. Moreover, some mice (25%) at 2 mo after split-dose irradiation had already developed thymic lymphomas in their thymuses. To characterize these thymic prelymphoma cells, the thymocytes from B10 Thy-1.1 mice 1 mo after irradiation were stained with anti-CD4 and anti-CD8 mAb and were sorted into four subpopulations. These fractionated cells were injected into the recipient thymuses to examine which subpopulation contained thymic prelymphoma cells. The results indicated that thymic prelymphoma cells existed mainly in CD4- CD8- and CD4- CD8+ thymocyte subpopulations and also in CD4+ CD8+ subpopulation. T cell lymphomas derived from CD4- CD8- prelymphoma cells had mainly CD4- CD8- or CD4- CD8+ phenotypes. T cell lymphomas developed from CD4- CD8+ prelymphoma cells mainly expressed CD4- CD8+ or CD4+ CD8+ phenotype. T cell lymphomas originating from CD4+ CD8+ prelymphoma cells were mainly CD4+ CD8+ but some CD4- CD8+ or CD4+ CD8- cells were also present. These thymic prelymphoma cells were further characterized phenotypically in relation to their expression of the marker defined by the mAb against J11d marker and TL-2 (thymus-leukemia) Ag, which is not expressed on normal thymocytes of B10.Thy-1.2 or B10.Thy-1.1 strain, but appears on the thymocytes of lymphomagenic irradiated mice. The results indicated that the prelymphoma cells existed in J11d+, TL-2+ cells

  9. Studies on radiation-induced thymic lymphomagenesis in B10 strain mice

    International Nuclear Information System (INIS)

    Muto, Masahiro

    1989-01-01

    Using B10.Thy 1 congenic strain mice, we reexamined the earlier results by Kaplan and others that lymphomas could develop from lymphocytes present in the nonirradiated parental thymuses grafted into thymectomized, fractionally irradiated H-2 semiincompatible recipient mice. The results indicated that 37 out of 91 thymectomized and irradiated B10.Thy 1.2 mice developed lymphomas of which 75 % were shown to have originated from grafted thymuses. The evidence was not obtained that supported the involvement of endogenous MuLV or some kind of transmissible agents during thymic lymphomagenesis. We found, with intrathymic injection assay, that 'preneoplastic' cells that will eventually develop into thymic lymphomas under the influence of thymic microenvironment first appeared in the thymuses about 4-8 days after irradiation. These thymic prelymphoma cells 'thymus-dependent' preneoplastic cells were detected in 26.1 % of the test donor thymuses when examined at 14 days and in more than 63 % 21 and 31 days after irradiation. It was found that lymphomagenic irradiation resulted in the anomalous appearance of CD4 + and/or CD8 + thymocytes bearing IL-2 receptor (IL-2R) which were different from normal thymocyte subpopulations. Thymic prelymphoma cells existed mainly in CD4 - CD8 - and CD4 - CD8 + thymocyted subpopulations and also in CD4 + CD8 + subpopulation. T cell lymphomas derived from CD4 - CD8 - prelymphoma cells had mainly CD4 - CD8 - or CD4 - CD8 + phenotypes. T cell lymphomas developed from CD4 - CD8 + prelymphoma cells mainly expressed CD4 - CD8 + or CD4 + CD8 + phenotype. T cell lymphomas originated from CD4 + CD8 + prelymphoma cells were mainly CD4 + CD8 + but some CD4 - CD8 + or CD4 + CD8 - cells were also present. These T cell lymphomas expressed IL-2R on various levels. The development of thymic prelymphoma cells is discussed in view of thymocyte differentiation. (J.P.N)

  10. Physics escape room as an educational tool

    Science.gov (United States)

    Vörös, Alpár István Vita; Sárközi, Zsuzsa

    2017-12-01

    Escape rooms have flourished in the last decade. These are adventure games in which players work together to solve puzzles using hints, clues and a strategy to escape from a locked room. In many cases they use different phenomena related to physics. Hence the idea of using escape rooms in science centers or even in classroom activities. Escape rooms are designed for one single team of players, the method is more suitable for activities in a science centre. In our paper, we show that escape rooms' puzzle solving methods could be used in physics classroom activities as well, taking into account that several teams have to work together in the same room/place. We have developed an educational escape game for physics of fluids, as this topic is left out from the Romanian high-school curriculum. We have tried out our game during the project week called "Şcoala altfel" ("school in a different way") and in a physics camp for gifted students. We present the designed physics escape game and the results.

  11. Adipocyte and leptin accumulation in tumor-induced thymic involution.

    Science.gov (United States)

    Lamas, Alejandro; Lopez, Elena; Carrio, Roberto; Lopez, Diana M

    2016-01-01

    Cell-mediated immunity is an important defense mechanism against pathogens and developing tumor cells. The thymus is the main lymphoid organ involved in the formation of the cell-mediated immune response by the maturation and differentiation of lymphocytes that travel from the bone marrow, through the lymphatic ducts, to become T lymphocytes. Thymic involution has been associated with aging; however, other factors such as obesity, viral infection and tumor development have been shown to increase the rate of shrinkage of this organ. The heavy infiltration of adipocyte fat cells has been reported in the involuted thymuses of aged mice. In the present study, the possible accumulation of such cells in the thymus during tumorigenesis was examined by immunohistochemistry. A significant number of adipocytes around and infiltrating the thymuses of tumor-bearing mice was observed. Leptin is a pro-inflammatory adipocytokine that enhances thymopoiesis and modulates T cell immune responses. The levels of leptin and adiponectin, another adipocytokine that has anti-inflammatory properties, were examined by western blot analysis. While no changes were observed in the amounts of adiponectin present in the thymuses of the normal and tumor-bearing mice, significantly higher levels of leptin were detected in the thymocytes of the tumor-bearing mice. This correlated with an increase in the expression of certain cytokines, such as interleukin (IL)-2, interferon (IFN)-γ and granulocyte-macrophage colony-stimulating factor (GM-CSF). The co-culture of thymocytes isolated from normal mice with ex vivo isolated adipocytes from tumor-bearing mice yielded similar results. Our findings suggest that the infiltration and accumulation of adipocytes in the thymuses of tumor-bearing mice play an important role in their altered morphology and functions.

  12. The molecular biology of radiation-induced carcinogenesis: thymic lymphoma, myeloid leukaemia and osteosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Janowski, M [Centre d' Etude de l' Energie Nucleaire, Mol (Belgium); Cox, R [Medical Research Council, Harwell (UK). Radiobiological Research Unit; Strauss, P G [GSF, Neuherberg (Germany, F.R.). Abt. fuer Molekulare Zellpathologie

    1990-04-01

    In mice, external X- or {gamma}-irradiation may induce thymic lymphomas or myeloid leukaemias, while bone-seeking {alpha}-emitters may induce osteosarcomas, and to a lesser extent acute myeloid leukaemia. The paper reviews briefly some experimental data in respect to molecular mechanisms underlying these radio-carcinogenic processes. Thymic lymphomagenesis proceeds by an indirect mechanism in which recombinant proviruses could be involved. Myeloid leukaemogenesis is characterized by a very early putative initiating event, consisting of non-random rearrangements and/or deletions of chromosome 2. Osteosarcomagenesis in mice is often associated with the expression of proviruses, and the tumors often contain somatically acquired proviruses. (UK).

  13. A pediatric case of life-threatening airway obstruction caused by a cervicomediastinal thymic cyst

    Energy Technology Data Exchange (ETDEWEB)

    Komura, Makoto; Kanamori, Yutaka; Sugiyama, Masahiko; Iwanaka, Tadashi [University of Tokyo Hospital, Department of Pediatric Surgery, Tokyo (Japan); Fukushima, Noriyoshi [University of Tokyo Hospital, Department of Pathology, Tokyo (Japan)

    2010-09-15

    Most patients with thymic cysts complain of a slowly enlarging, asymptomatic cervical mass. Only 6-10% suffer dysphagia, dyspnoea, stridor, cervical pain or vocal paralysis. In some rare cases sudden onset of severe dyspnoea or asphyxia is the first symptom, especially in neonates and small infants. We report a unique case of a 20-month-old child, who required emergency tracheal intubation due to asphyxia. Cervicomediastinal thymic cyst might need to be included in causes of life-threatening airway obstruction in young children. (orig.)

  14. Detection of chemotherapy-induced thymic changes in patients with metastasised testicular tumors by computed tomography

    International Nuclear Information System (INIS)

    Hendrickx, P.; Doehring, W.

    1989-01-01

    Serial thoracic CT scans of 100 patients suffering from testicular cancer revealed that the thymus appears to atrophy temporarily during administration of cytostatic agents. About two months after cessation of chemotherapy rebound enlargement of the thymus occurs and persists for about two years followed by a slow involution. Using a semiquantitative score system, thymic CT images of these patients were compared with that of 100 patients suffering from other malignancies, 100 patients without malignant disease and 52 patients with myasthenia gravis, taking into account the age-related changes of the size of the organ. Rebound thymic enlargement should not be misinterpreted as metastatic lymph nodes. (orig.) [de

  15. Detection of chemotherapy-induced thymic changes in patients with metastasised testicular tumors by computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickx, P.; Doehring, W.

    1989-03-01

    Serial thoracic CT scans of 100 patients suffering from testicular cancer revealed that the thymus appears to atrophy temporarily during administration of cytostatic agents. About two months after cessation of chemotherapy rebound enlargement of the thymus occurs and persists for about two years followed by a slow involution. Using a semiquantitative score system, thymic CT images of these patients were compared with that of 100 patients suffering from other malignancies, 100 patients without malignant disease and 52 patients with myasthenia gravis, taking into account the age-related changes of the size of the organ. Rebound thymic enlargement should not be misinterpreted as metastatic lymph nodes.

  16. A Model for SEP Escape

    Science.gov (United States)

    Antiochos, S. K.; Masson, S.; DeVore, C. R.

    2012-01-01

    Magnetic reconnection in the solar atmosphere is believed to be the driver of most solar explosive phenomena. Therefore, the topology of the coronal magnetic field is central to understanding the solar drivers of space weather. Of particular importance to space weather are the impulsive Solar Energetic particles that are associated with some CME/eruptive flare events. Observationally, the magnetic configuration of active regions where solar eruptions originate appears to agree with the standard eruptive flare model. According to this model, particles accelerated at the flare reconnection site should remain trapped in the corona and the ejected plasmoid. However, flare-accelerated particles frequently reach the Earth long before the CME does. We present a model that may account for the injection of energetic particles onto open magnetic flux tubes connecting to the Earth. Our model is based on the well-known 2.5D breakout topology, which has a coronal null point (null line) and a four-flux system. A key new addition, however, is that we include an isothermal solar wind with open-flux regions. Depending on the location of the open flux with respect to the null point, we find that the flare reconnection can consist of two distinct phases. At first, the flare reconnection involves only closed field, but if the eruption occurs close to the open field, we find a second phase involving interchange reconnection between open and closed. We argue that this second reconnection episode is responsible for the injection of flare-accelerated particles into the interplanetary medium. We will report on our recent work toward understanding how flare particles escape to the heliosphere. This work uses high-resolution 2.5D MHD numerical simulations performed with the Adaptively Refined MHD Solver (ARMS).

  17. Narrow Escape of Interacting Diffusing Particles

    Science.gov (United States)

    Agranov, Tal; Meerson, Baruch

    2018-03-01

    The narrow escape problem deals with the calculation of the mean escape time (MET) of a Brownian particle from a bounded domain through a small hole on the domain's boundary. Here we develop a formalism which allows us to evaluate the nonescape probability of a gas of diffusing particles that may interact with each other. In some cases the nonescape probability allows us to evaluate the MET of the first particle. The formalism is based on the fluctuating hydrodynamics and the recently developed macroscopic fluctuation theory. We also uncover an unexpected connection between the narrow escape of interacting particles and thermal runaway in chemical reactors.

  18. Dynamic Escape Routes for Naval Ships

    National Research Council Canada - National Science Library

    Villalonga, Francisco J

    2005-01-01

    This thesis addresses the problem of optimal evacuation of a naval ship. We propose the use of a dynamic escape-route system which employs a signaling system to adapt the emergency egress process to the instigating contingency...

  19. St.Petersburg Escape Experience Tour

    OpenAIRE

    Palagina, Mariia; Zhak, Svetlana

    2017-01-01

    The growing popularity of Russia as a tourist destination and the high interest towards escape rooms and quests opens new business opportunities and market niches. The aim of this thesis is to develop a tourist product based on the new escape room tourism concept combining the historical, cultural and game experiences. The choice of the theme and destination was determined by the authors’ personal backgrounds and the destination proximity to Finland. The theoretical research was implement...

  20. Anti-apoptotic signature in thymic squamous cell carcinomas - functional relevance of anti-apoptotic BIRC3 expression in the thymic carcinoma cell line 1889c

    Directory of Open Access Journals (Sweden)

    Bei eHuang

    2013-12-01

    Full Text Available The molecular pathogenesis of thymomas and thymic carcinomas (TCs is poorly understood and results of adjuvant therapy are unsatisfactory in case of metastatic disease and tumor recurrence. For these clinical settings, novel therapeutic strategies are urgently needed. Recently, limited sequencing efforts revealed that a broad spectrum of genes that play key roles in various common cancers are rarely affected in thymomas and thymic carcinomas, suggesting that other oncogenic principles might be important. This made us re-analyze historic expression data obtained in a spectrum of thymomas and thymic squamous cell carcinomas (TSCC with a custom made cDNA microarray. By cluster analysis, different anti-apoptotic signatures were detected in type B3 thymoma and TSCC, including overexpression of BIRC3 in TSCCs. This was confirmed by qRT-PCR in the original and an independent validation set of tumors. In contrast to several other cancer cell lines, the BIRC3-positive TSCC cell line, 1889c showed spontaneous apoptosis after BIRC3 knock-down. Targeting apoptosis genes is worth testing as therapeutic principle in TSCC.

  1. Thymic function in the regulation of T cells, and molecular mechanisms underlying the modulation of cytokines and stress signaling (Review).

    Science.gov (United States)

    Yan, Fenggen; Mo, Xiumei; Liu, Junfeng; Ye, Siqi; Zeng, Xing; Chen, Dacan

    2017-11-01

    The thymus is critical in establishing and maintaining the appropriate microenvironment for promoting the development and selection of T cells. The function and structure of the thymus gland has been extensively studied, particularly as the thymus serves an important physiological role in the lymphatic system. Numerous studies have investigated the morphological features of thymic involution. Recently, research attention has increasingly been focused on thymic proteins as targets for drug intervention. Omics approaches have yielded novel insights into the thymus and possible drug targets. The present review addresses the signaling and transcriptional functions of the thymus, including the molecular mechanisms underlying the regulatory functions of T cells and their role in the immune system. In addition, the levels of cytokines secreted in the thymus have a significant effect on thymic functions, including thymocyte migration and development, thymic atrophy and thymic recovery. Furthermore, the regulation and molecular mechanisms of stress‑mediated thymic atrophy and involution were investigated, with particular emphasis on thymic function as a potential target for drug development and discovery using proteomics.

  2. Genetic Regulation of Development of Thymic Lymphomas Induced by N‐Propyl‐N‐nitrosourea in the Rat

    Science.gov (United States)

    Fukami, Hiroko; Nishimura, Mayumi; Matsuyama, Mutsushi

    1995-01-01

    To clarify the linkage between Hbb and Tls‐1 (thymic lymphoma susceptible‐1) loci and to investigate other loci concerned in thymic lymphomagenesis, the BUF/Mna rat, which is highly sensitive to the lymphomagenic activity of N‐propyl‐N‐nitrosourea (PNU), the WKY/NCrj rat, reported to be resistant, and their cross offspring were subjected to genetic analysis. F1 hybrid and backcross generations were raised from the 2 strains, and 6 genetic markers including Hbb were analyzed in individuals of the backcross generation. However, no linkage between Hbb and Tls‐1 loci could be demonstrated since WKY rats also developed a high incidence of thymic lymphomas in response to PNU. Nevertheless, thymic lymphomas developed more rapidly and reached a larger size in the BUF rats. F1 rats expressed a rather rapid and large tumor growth phenotype, while the [(WKY × BUF) × WKY] backcross generation consisted of rats with either rapidly growing or slowly growing tumors. It was thus concluded that rapid development of thymic lymphomas is determined by a gene, provisionally designated Tls‐3. Analysis of the relationship between 6 genetic markers and development of thymic lymphoma in the backcross generation demonstrated that the Tls‐3 locus is loosely linked to the Gc locus, suggesting a possible location on rat chromosome 14. Tls‐3 may not be identical with Tls‐1 and other genes known to be relevant to thymic tumors, but its relationship with Tls‐2 remains obscure. PMID:7559080

  3. Thymic stromal lymphopoietin as a novel mediator amplifying immunopathology in rheumatic disease

    NARCIS (Netherlands)

    Hillen, Maarten R.; Radstake, Timothy R. D. J.; Hack, Cornelis E.; van Roon, Joel A. G.

    2015-01-01

    Thymic stromal lymphopoietin (TSLP) is an IL-7-related cytokine that has been studied extensively in atopic diseases and more recently in various rheumatic disorders. It is involved in T cell development in the thymus and promotes homeostatic T cell expansion by classical dendritic cells. However,

  4. Primary thymic extranodal marginal zone B cell lymphoma as an incidental finding in a Caucasian woman

    DEFF Research Database (Denmark)

    Krogh Petersen, Jeanette; Larsen, Thomas Stauffer; Møller, Michael Boe

    2015-01-01

    Primary thymic extranodal marginal zone B cell lymphoma (TML) is an extremely rare lymphoma strongly associated with autoimmune disease. We report an exceedingly rare case of TML found in a non-Asian population. TML was found incidentally in a 60-year-old Caucasian woman with a short history...

  5. Case Report: CT diagnosis of thymic remnant cyst/thymopharyngeal duct cyst

    International Nuclear Information System (INIS)

    Daga, Bipin V; Chaudhary, VA; Dhamangaokar, VB

    2009-01-01

    A 4-year-old boy presented with history of left anterolateral neck swelling since birth. He was clinically diagnosed to have a branchial cleft cyst. A CT scan revealed findings suggestive of a thymic remnant cyst. The lesion was excised and the diagnosis was confirmed by histopathology

  6. The effect of early measles vaccination on thymic size. A randomized study from Guinea-Bissau

    DEFF Research Database (Denmark)

    Christensen, Lone Damkjær; Eriksen, Helle Brander; Biering-Sørensen, Sofie

    2014-01-01

    In low-income countries early measles vaccine (MV) is associated with reduced child mortality which cannot be explained by prevention of measles. A large thymus gland in infancy is also associated with reduced mortality. We hypothesized that early MV is associated with increased thymic size. Within...

  7. Spleen and thymic sonography as estimator of the immune response in children with repeated infections

    International Nuclear Information System (INIS)

    Rabaza, Jesus; Fundora, Hermes; Rodriguez, Alexis; Hernandez, Maria de los Angeles

    2010-01-01

    The spleen is a secondary lymphoid organ. The spleen has many functions: IgM class antibody production and phagocytosis of encapsulated bacteria. We propose to measure the dimensions of the spleen in children with repeated infections, in order to describe them as a diagnosis marker and to explore the probable correlation between the thymic characteristics and the dimensions of the spleen. We study 81 patients that attended the consultation of Immunology from Aballi hospital with repeated infections and they were from 8 months to 9 years old. Children with nutritional value up to the third percentile and those taking steroids 45 days before the study were excluded. We measured the thymic and splenic areas by mediastinal and abdominal echography. The length, the splenic index and the weight are less in patients with repeated infections. These data were significant in 12 to 23 month of age group. The length and the splenic index were less in patients with depletion of thymic area. The sonographic evaluation of the spleen is very important in patients from 1 to 2 years old and in patients with thymic depletion, because they are on the age of vaccine administration according to the Cuban schedule and having affected a main organ for immune response might be a reason for them to show a deficient response and need special schedules

  8. Elevation of oleate-activated phospholipase D activity during thymic atrophy

    Science.gov (United States)

    Lee, Youngkyun; Song, Soo-Mee; Park, Heung Soon; Kim, Sungyeol; Koh, Eun-Hee; Choi, Myung Sun; Choi, Myung-Un

    2002-01-01

    Various phospholipases are thought to be associated with the in vitro apoptosis of thymocytes. In the present study, the in vivo phospholipase D (PLD) activity of rat thymus was studied after whole-body X-irradiation or injection of dexamethasone (DEX). Using exogenous [14C]dipalmitoyl phosphatidylcholine (PC) as the substrate, an elevation of oleate-activated PLD activity was observed during thymic atrophy. The activity increases were sevenfold at 48 hr after 5-Gy irradiation and fourfold at 72 hr after injection of 5 mg/kg DEX. The elevation of PLD activity appeared to parallel extensive thymus shrinkage. An increased level of thymic phosphatidic acid (PA), the presumed physiological product of PLD action on PC, was also detected. By comparing the acyl chains of PA with those of other phospholipids, PA appeared to originate from PC. To assess the role of PLD during thymic atrophy, thymocytes and stromal cells were isolated. Although thymocytes themselves exhibited significant PLD activation, the major elevation in PLD activity (greater than fourfold) was found in isolated stromal cells. PLD was also activated during in vitro phagocytosis of apoptotic thymocytes by the macrophage-like cell line P388D1. This in vitro phagocytosis was significantly inhibited by PLD action blockers, such as 2,3-diphosphoglycerate and 1-butanol. These observations strongly suggest that the alteration of oleate-activated PLD activity is part of an in vivo event in the progression of thymic atrophy, including phagocytic clearance of apoptotic thymocytes. PMID:12460188

  9. Doubling time of thymic epithelial tumours on CT: correlation with histological subtype

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Jooae; Lee, Sang Min; Kim, Namkug; Do, Kyung-Hyun; Seo, Joon Beom [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Songpa-gu, Seoul (Korea, Republic of); Lim, Soyeoun [Ulsan University Hospital, Department of Radiology, University of Ulsan College of Medicine, Ulsan (Korea, Republic of); Choi, Se Hoon [University of Ulsan College of Medicine, Department of Thoracic and Cardiovascular Surgery, Seoul (Korea, Republic of)

    2017-10-15

    We retrospectively evaluated the doubling time (DT) of thymic epithelial tumours (TET) according to the histological subtype on CT. From January 2005 to June 2016, we enrolled 53 patients who had pathologically confirmed TET and at least two CT scans. Tumour size was measured using a two-dimensional method, and the DT was calculated. DTs were compared among histological subtypes, and factors associated with rapid tumour growth (DT <180 days) were assessed. In 42 of the 53 patients (79.2%) the tumours showed interval growth (>2 mm) during follow-up. The median DT for all tumours was 400 days (range 48-1,964 days). There were no significant differences in DT in relation to histological subtype (p = 0.177). When TETs were recategorized into three groups, i.e. low-risk thymomas (types A, AB, B1), high-risk thymomas (types B2, B3), and thymic carcinoma, DT was significantly different among the groups (median DT 436, 381 and 189 days, respectively; p = 0.031). Histological subtype (type B3 and thymic carcinoma) was the single independent predictor of rapid tumour growth. The majority of TETs grew during follow-up with variable and relatively slow growth rates. Histological features of aggressive behaviour significantly correlated with a decreased DT and rapid growth. circle The majority of thymic epithelial tumours grew during follow-up (79.2%, 42/53). (orig.)

  10. Deregulation of mTOR signaling is involved in thymic lymphoma development in Atm-/- mice

    International Nuclear Information System (INIS)

    Kuang, Xianghong; Shen, Jianjun; Wong, Paul K.Y.; Yan, Mingshan

    2009-01-01

    Abnormal thymocyte development with thymic lymphomagenesis inevitably occurs in Atm-/- mice, indicating that ATM plays a pivotal role in regulating postnatal thymocyte development and preventing thymic lymphomagenesis. The mechanism for ATM controls these processes is unclear. We have shown previously that c-Myc, an oncoprotein regulated by the mammalian target of rapamycin (mTOR), is overexpressed in Atm-/- thymocytes. Here, we show that inhibition of mTOR signaling with its specific inhibitor, rapamycin, suppresses normal thymocyte DNA synthesis by downregulating 4EBP1, but not S6K, and that 4EBP1 phosphorylation and cyclin D1 expression are coordinately increased in Atm-/- thymocytes. Administration of rapamycin to Atm-/- mice attenuates elevated phospho-4EBP1, c-Myc and cyclin D1 in their thymocytes, and delays thymic lymphoma development. These results indicate that mTOR downstream effector 4EBP1 is essential for normal thymocyte proliferation, but deregulation of 4EBP1 in Atm deficiency is a major factor driving thymic lymphomagenesis in the animals.

  11. Micronodular thymic neoplasms: case series and literature review with emphasis on the spectrum of differentiation.

    Science.gov (United States)

    Mneimneh, Wadad S; Gökmen-Polar, Yesim; Kesler, Kenneth A; Loehrer, Patrick J; Badve, Sunil

    2015-11-01

    We report nine cases of micronodular thymoma with lymphoid B-cell hyperplasia and one case of micronodular thymic carcinoma with lymphoid hyperplasia from our institution. For a better understanding of these rare tumors, clinical records, and histological features of these cases were reviewed, with detailed review of additional 64 literature cases of micronodular thymic neoplasms. The joint analysis identified 64 cases of micronodular thymoma with lymphoid B-cell hyperplasia and 9 cases of micronodular thymic carcinoma with lymphoid hyperplasia. Both groups revealed slight male predilection, with male:female ratio of 1.3:1 and 5:4, and occurred at >40 years of age, with a mean of 64 (41-83) and 62 (42-78) years, respectively. Myasthenia gravis was noted in 3/64 (5%) and 1/9 (11%) patients, respectively. Other systemic, disimmune, or hematologic disorders were noted in 6/64 (9%) and 1/9 (11%) patients, respectively. Components of conventional thymoma were reported in 11/64 (17%) micronodular thymomas with lymphoid B-cell hyperplasia, with transitional morphology between the two components in most of them. Cellular morphology was predominantly spindle in micronodular thymoma with lymphoid B-cell hyperplasia when specified (30/43), and epithelioid in micronodular thymic carcinoma with lymphoid hyperplasia (6/9), and cytological atypia was more encountered in the latter. Dedifferentiation/transformation from micronodular thymoma with lymphoid B-cell hyperplasia to micronodular thymic carcinoma with lymphoid hyperplasia seems to occur in a small subset of cases. Three cases of micronodular thymomas with lymphoid B-cell hyperplasia were described with co-existent low-grade B-cell lymphomas. Follow-up data were available for 30 micronodular thymomas with lymphoid B-cell hyperplasia and 6 micronodular thymic carcinomas with lymphoid hyperplasia, with a mean of 47 (0.2-180) months and 23 (3-39) months, respectively. Patients were alive without disease, except for five

  12. A case of congenital Langerhans cell histiocytosis with skin and thymic lesions: Exploring the prognostic value of thymus involvement

    Directory of Open Access Journals (Sweden)

    M.M. Escudero-Góngora

    2016-10-01

    Full Text Available Thymus evaluation is not included in the guidelines of the Histiocyte Society, so its prevalence, management and prognosis are not well established. We present a newborn with self-healing cutaneous LCH and thymic involvement that was evaluated with a thoracic ultrasound. With the current evidence we are unable to predict the prognosis of the thymus association in neonatal LCH. We suggest that performing thymic ultrasound study, which is a non-invasive technique, would allow us to know the incidence of thymic involvement and its role on prognosis.

  13. Chest roentgenographic findings of thymic size and shape in respiratory distress syndrome

    International Nuclear Information System (INIS)

    Oh, Young Ho; Yoon, Sung Do; Sung, Ki Yeal; Park, Seog Hee; Kim, Jong Woo; Bahk, Yong Whee

    1984-01-01

    Thymic size can be affected by both exogenous and endogenous glucocorticoids. Development of the respiratory distress syndrome (RDS) is influenced by adrenal cortical function. Thus, thymic size in RDS is considered to be enlarged due to decreased adrenal cortical function. To find whether the presence of RDS correlates with the thymus, the size and shape of the thymus were evaluated in the radiographs of premature infants with RDS, without RDS (control prematurity) and normal infants. The subjects were consisted of chest films of Korean premature infants, 120 with RDS, 60 without RDS, and 60 of normal infants taken at the Department of Radiology, Our Lady of Mercy Hospital during the period of 62 months since January 1978. Relative size of the thymus was determine by cardiothymic/thoracic ratio (CT /T ratio). Grading and location of the thymic prominence as well as incidence of the shape were examined. And all the relations among the radiographs of RDS, control prematurity and normal infants were analyzed. The results were as follows: 1. The CT/T ratio of premature infants with RDS was significantly greater than that of control prematurity and normal infants (P< 0.01). 2. The incidence of bilateral thymic prominence was more frequent in premature infant with RDS than in control prematurity and normal infants (P<0.05). 3. The frequency of thymic prominence was greater in the right than left side in all the three groups (P<0.05). 4. As in the shape of the thymus, a rounded type was most frequent, and a triangular type was least frequent in all three groups. 5. Incident of RDS was very low (9.8%) when the CT/T ratio is below 0.3 and it was very high (90.9%) when the CT/T ratio is above 0.49.

  14. Cerebrospinal Fluid HIV Escape from Antiretroviral Therapy.

    Science.gov (United States)

    Ferretti, Francesca; Gisslen, Magnus; Cinque, Paola; Price, Richard W

    2015-06-01

    CNS infection is a nearly constant facet of systemic CNS infection and is generally well controlled by suppressive systemic antiretroviral therapy (ART). However, there are instances when HIV can be detected in the cerebrospinal fluid (CSF) despite suppression of plasma viruses below the clinical limits of measurement. We review three types of CSF viral escape: asymptomatic, neuro-symptomatic, and secondary. The first, asymptomatic CSF escape, is seemingly benign and characterized by lack of discernable neurological deterioration or subsequent CNS disease progression. Neuro-symptomatic CSF escape is an uncommon, but important, entity characterized by new or progressive CNS disease that is critical to recognize clinically because of its management implications. Finally, secondary CSF escape, which may be even more uncommon, is defined by an increase of CSF HIV replication in association with a concomitant non-HIV infection, as a consequence of the local inflammatory response. Understanding these CSF escape settings not only is important for clinical diagnosis and management but also may provide insight into the CNS HIV reservoir.

  15. Escape of magnetic toroids from the Sun

    International Nuclear Information System (INIS)

    Bieber, John W.; Rust, David M.

    1996-01-01

    Analysis of heliospheric magnetic fields at 1 AU shows that 10 24 Mx of net toroidal flux escapes from the Sun per solar cycle. This rate is compared with the apparent rate of flux emergence at the solar surface, and it is concluded that escaping toroids will remove at least 20% of the emerging flux, and may remove as much as 100% of emerging flux if multiple eruptions occur on the toroids. The data imply that flux escapes the Sun with an efficiency far exceeding Parker's upper limit estimate of 3%. Toroidal flux escape is almost certainly the source of the observed overwinding of the interplanetary magnetic field spiral. Two mechanisms to facilitate net flux escape are discussed: helicity charging to push open the fields and flux transport with reconnection to close them off. We estimate the Sun will shed ∼2x10 45 Mx 2 of magnetic helicity per solar cycle, leading to a mean helicity density of 100 Mx 2 cm -3 at 1 AU, which agrees well with observations

  16. Thermal escape from extrasolar giant planets.

    Science.gov (United States)

    Koskinen, Tommi T; Lavvas, Panayotis; Harris, Matthew J; Yelle, Roger V

    2014-04-28

    The detection of hot atomic hydrogen and heavy atoms and ions at high altitudes around close-in extrasolar giant planets (EGPs) such as HD209458b implies that these planets have hot and rapidly escaping atmospheres that extend to several planetary radii. These characteristics, however, cannot be generalized to all close-in EGPs. The thermal escape mechanism and mass loss rate from EGPs depend on a complex interplay between photochemistry and radiative transfer driven by the stellar UV radiation. In this study, we explore how these processes change under different levels of irradiation on giant planets with different characteristics. We confirm that there are two distinct regimes of thermal escape from EGPs, and that the transition between these regimes is relatively sharp. Our results have implications for thermal mass loss rates from different EGPs that we discuss in the context of currently known planets and the detectability of their upper atmospheres.

  17. Bilateral cervical ectopic thymic nodules with accessory thyroid tissue and an ectopic parathyroid in the neck region

    Directory of Open Access Journals (Sweden)

    Wea-Lung Lin

    2011-03-01

    Full Text Available Some remnants of thymic tissue may be deposited along the pathway of the descent of the neck during embryologic development of the thymus. Ectopic thymic tissue is usually deposited along the pathway from the mandibular angle to the manubrium of the sternum. Most reported cases of an ectopic thymus occurred in children, and cases are less common in adults. We report a 26-year-old woman, who was incidentally found to have 2 neck nodules on the posterior side of the bilateral upper pole of the thyroid gland while undergoing a subtotal thyroidectomy. The left-side neck nodule showed accessory thyroid follicles intermixed with ectopic thymic tissue, and the right-side neck nodule was ectopic parathyroid tissue together with ectopic thymic tissue.

  18. Can a Proper T-Cell Development Occur in an Altered Thymic Epithelium? Lessons From EphB-Deficient Thymi

    Directory of Open Access Journals (Sweden)

    Juan José Muñoz

    2018-04-01

    Full Text Available For a long time, the effects of distinct Eph tyrosine kinase receptors and their ligands, ephrins on the structure, immunophenotype, and development of thymus and their main cell components, thymocytes (T and thymic epithelial cells (TECs, have been studied. In recent years, the thymic phenotype of mutant mice deficient in several Ephs and ephrins B has been determined. Remarkably, thymic stroma in these animals exhibits important defects that appear early in ontogeny but little alterations in the proportions of distinct lymphoid cell populations. In the present manuscript, we summarize and extend these results discussing possible mechanisms governing phenotypical and functional thymocyte maturation in an absence of the critical T–TEC interactions, concluding that some signaling mediated by key molecules, such as MHCII, CD80, β5t, Aire, etc. could be sufficient to enable a proper maturation of thymocytes, independently of morphological alterations affecting thymic epithelium.

  19. Black holes escaping from domain walls

    International Nuclear Information System (INIS)

    Flachi, Antonino; Sasaki, Misao; Pujolas, Oriol; Tanaka, Takahiro

    2006-01-01

    Previous studies concerning the interaction of branes and black holes suggested that a small black hole intersecting a brane may escape via a mechanism of reconnection. Here we consider this problem by studying the interaction of a small black hole and a domain wall composed of a scalar field and simulate the evolution of this system when the black hole acquires an initial recoil velocity. We test and confirm previous results, however, unlike the cases previously studied, in the more general set-up considered here, we are able to follow the evolution of the system also during the separation, and completely illustrate how the escape of the black hole takes place

  20. Fate of thymic lymphocytes. [/sup 125/IudR and /sup 3/HTdR tracer studies in mice

    Energy Technology Data Exchange (ETDEWEB)

    Laissue, J A; Chanana, A D; Cronkite, E P; Joel, D D

    1976-01-01

    Data are summarized from a number of studies on the fate of thymic lymphocytes. Results are reported from studies in mice in which /sup 125/IudR and /sup 3/HTdR were used as tracers to study the production, maturation, migration, and life span of thymic lymphocytes. It is pointed out that thymus-derived cells constitute the majority of recirculating lymphocytes and that peripheral, differentiated thymus-derived lymphocytes exhibit a number of immunological functions. 114 references.

  1. Martian Atmospheric and Ionospheric plasma Escape

    Science.gov (United States)

    Lundin, Rickard

    2016-04-01

    Solar forcing is responsible for the heating, ionization, photochemistry, and erosion processes in the upper atmosphere throughout the lifetime of the terrestrial planets. Of the four terrestrial planets, the Earth is the only one with a fully developed biosphere, while our kin Venus and Mars have evolved into arid inhabitable planets. As for Mars, there are ample evidences for an early Noachian, water rich period on Mars. The question is, what made Mars evolve so differently compared to the Earth? Various hydrosphere and atmospheric evolution scenarios for Mars have been forwarded based on surface morphology, chemical composition, simulations, semi-empiric (in-situ data) models, and the long-term evolution of the Sun. Progress has been made, but the case is still open regarding the changes that led to the present arid surface and tenuous atmosphere at Mars. This presentation addresses the long-term variability of the Sun, the solar forcing impact on the Martian atmosphere, and its interaction with the space environment - an electromagnetic wave and particle interaction with the upper atmosphere that has implications for its photochemistry, composition, and energization that governs thermal and non-thermal escape. Non-thermal escape implies an electromagnetic upward energization of planetary ions and molecules to velocities above escape velocity, a process governed by a combination of solar EUV radiation (ionization), and energy and momentum transfer by the solar wind. The ion escape issue dates back to the early Soviet and US-missions to Mars, but the first more accurate estimates of escape rates came with the Phobos-2 mission in 1989. Better-quality ion composition measurement results of atmospheric/ionospheric ion escape from Mars, obtained from ESA Mars Express (MEX) instruments, have improved our understanding of the ion escape mechanism. With the NASA MAVEN spacecraft orbiting Mars since Sept. 2014, dual in-situ measurement with plasma instruments are now

  2. Photoperiodic modulation of local melatonin synthesis and its role in regulation of thymic homeostasis in Funambulus pennanti.

    Science.gov (United States)

    Gupta, Sameer; Haldar, Chandana

    2016-12-01

    The effect of photo-neuroendocrine system on the thymic (immune) functions is mediated by gonadal steroid and the pineal hormone melatonin. The present study explored the effect of photoperiod on the thymic melatonergic system and its role in protection of thymic T-cells from the testosterone induced seasonal oxidative stress and apoptosis. Exposure to long day-length (LD) was noted to decrease local (thymic) melatonin content and induce oxidative stress and apoptosis in the thymus. Increased peripheral level of testosterone upregulated the androgen receptor expression and, consequently reduced proliferation response of the thymocytes. Short day conditions (SD) however, reversed the effect of LD on the thymic physiology. Low level of testosterone was concomitant with diminished nitro-oxidative stress and decreased expression of redox sensitive factors (NF-κB, p53 and Bax/Bcl-2 ratio) in the thymus. SD retarded activation of caspase-3 resulting in procaspase-3 accumulation. Further, in vitro treatment of thymocytes with AR antagonist flutamide impaired the sensitivity of thymocytes to androgen and reversed the deleterious effects of testosterone on the proliferative and apoptotic responses of thymocytes. Therefore, it can be suggested that thymus derived melatonin protects thymic T-cells from testosterone induced seasonal oxidative stress, apoptosis and also acts as a potent paracrine factor for maintenance of redox status to ensure thymocyte survival. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Volume-based quantification using dual-energy computed tomography in the differentiation of thymic epithelial tumours: an initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Suyon; Hur, Jin; Im, Dong Jin; Suh, Young Joo; Hong, Yoo Jin; Lee, Hye-Jeong; Kim, Young Jin; Choi, Byoung Wook [Yonsei University College of Medicine, Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Seoul (Korea, Republic of); Han, Kyunghwa [Yonsei University College of Medicine, Yonsei Biomedical Research Institute, Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Seoul (Korea, Republic of); Kim, Dae Joon; Lee, Chang Young [Yonsei University College of Medicine, Department of Thoracic and Cardiovascular Surgery, Seoul (Korea, Republic of); Shin, Ha Young [Yonsei University College of Medicine, Department of Neurology, Seoul (Korea, Republic of)

    2017-05-15

    To investigate the diagnostic value of dual-energy computed tomography (DECT) in differentiating between low- and high-risk thymomas and thymic carcinomas. Our institutional review board approved this study, and patients provided informed consent. We prospectively enrolled 37 patients (20 males, mean age: 55.6 years) with thymic epithelial tumour. All patients underwent DECT. For quantitative analysis, two reviewers measured the following tumour parameters: CT attenuation value in contrast Hounsfield units (CHU), iodine-related HU and iodine concentration (mg/ml). Pathological results confirmed the final diagnosis. Of the 37 thymic tumours, 23 (62.2 %) were low-risk thymomas, five (13.5 %) were high-risk thymomas and nine (24.3 %) were thymic carcinomas. According to quantitative analysis, iodine-related HU and iodine concentration were significantly different among low-risk thymomas, high-risk thymomas and thymic carcinomas (median: 29.78 HU vs. 14.55 HU vs. 19.95 HU, p = 0.001 and 1.92 mg/ml vs. 0.99 mg/ml vs. 1.18 mg/ml, p < 0.001, respectively). DECT using a quantitative analytical method based on iodine concentration measurement can be used to differentiate among thymic epithelial tumours using single-phase scanning. (orig.)

  4. Do the visual conditions at the point of escape affect European sea bass escape behavior?

    Directory of Open Access Journals (Sweden)

    I.E. PAPADAKIS

    2013-03-01

    Full Text Available European sea bass (Dicentrarchus labrax, an important species for the Mediterranean aquaculture industry, has been reported to escape from sea cage installations. Fish escapes are caused mainly by operational and technical failures that eventually result into a creation of a tear. Escapees may interact with wild stocks through interbreeding, transfer of pathogens and competition for food. The aim of this study was to examine at which extent the presence of a visible obstacle close to a tear on the net have an influence on sea bass propensity to escape. Fish were initially confined into small sea cages, with a tear at one side. The escape behavior was tested under experimental conditions. It is clearly demonstrated that sea bass was able to locate a tear on the net pen, immediately after its appearance. Crossings occurred in all cages, in singles or in a series of up to seven individuals. The presence of an obstacle close to the net tear altered the escape behavior of D. labrax resulting in a delay that eventually reduced the escape rate. Concluding, it is highly recommended that sea bass cages should be kept internally the culture array. Furthermore, the placement of artificial obstacles close to the sea cages could be an efficient practice that mitigates the escape risk after severe environmental conditions.

  5. Learning from escaped prescribed fire reviews

    Science.gov (United States)

    Anne E. Black; Dave Thomas; James Saveland; Jennifer D. Ziegler

    2011-01-01

    The U.S. wildland fire community has developed a number of innovative methods for conducting a review following escape of a prescribed fire (expanding on the typical regional or local reviews, to include more of a learning focus - expanded After Action Reviews, reviews that incorporate High Reliability Organizing, Facilitated Learning Analyses, etc). The stated purpose...

  6. Genomics of Stress Escape in Arabidopsis Thaliana

    NARCIS (Netherlands)

    Das, D.

    2016-01-01

    In nature, two highly diverse environmental signals, flooding and shade, sensed through their own unique receptor systems, share physiological and molecular similarities in the context of accelerated shoot elongation in plants (a conserved stress-escape strategy), suggesting a possible cross-talk

  7. Centrifugally Stimulated Exospheric Ion Escape at Mercury

    Science.gov (United States)

    Delcourt, Dominique; Seki, K.; Terada, N.; Moore, Thomas E.

    2012-01-01

    We investigate the transport of ions in the low-altitude magnetosphere magnetosphere of Mercury. We show that, because of small spatial scales, the centrifugal effect due to curvature of the E B drift paths can lead to significant particle energization in the parallel direction. We demonstrate that because of this effect, ions with initial speed smaller than the escape speed such as those produced via thermal desorption can overcome gravity and escape into the magnetosphere. The escape route of this low-energy exosphere originating material is largely controlled by the magnetospheric convection rate. This escape route spreads over a narrower range of altitudes when the convection rate increases. Bulk transport of low-energy planetary material thus occurs within a limited region of space once moderate magnetospheric convection is established. These results suggest that, via release of material otherwise gravitationally trapped, the E B related centrifugal acceleration is an important mechanism for the net supply of plasma to the magnetosphere of Mercury.

  8. Pade approximant calculations for neutron escape probability

    International Nuclear Information System (INIS)

    El Wakil, S.A.; Saad, E.A.; Hendi, A.A.

    1984-07-01

    The neutron escape probability from a non-multiplying slab containing internal source is defined in terms of a functional relation for the scattering function for the diffuse reflection problem. The Pade approximant technique is used to get numerical results which compare with exact results. (author)

  9. Net escapement of Antartic krill in trawls

    DEFF Research Database (Denmark)

    Krafft, B.A.; Krag, Ludvig Ahm; Herrmann, Bent

    This document describes the aims and methodology of a three year project (commenced in 2012) entitled Net Escapement of Antarctic krill in Trawls (NEAT). The study will include a morphology based mathematical modeling (FISHSELECT) of different sex and maturity groups of Antarctic krill (Euphausia...

  10. Immune recovery in acute and chronic HIV infection and the impact of thymic stromal lymphopoietin

    DEFF Research Database (Denmark)

    Gelpi, Marco; Hartling, Hans J; Thorsteinsson, Kristina

    2016-01-01

    was comparable in all groups, and no differences in immune homeostasis were found between primary HIV infection and early presenters, whereas differences in absolute counts and proportions of CD4+ T cell subpopulations were found between primary HIV infection and late presenters. TSLP was elevated in primary HIV...... thymic output, but not with immune recovery. These findings indicate a possible role of TSLP in immune homeostasis in HIV infection but do not support TSLP to affect immune recovery in primary HIV infection.......BACKGROUND: Symptomatic primary HIV infection is associated with an adverse prognosis, and immediate initiation of combination antiretroviral therapy (cART) is recommended. However, little is known about immunological predictors of immune recovery. Thymic Stromal Lymphopoietin (TSLP) is a cytokine...

  11. Factors associated with thymic size at birth among low and normal birth-weight infants

    DEFF Research Database (Denmark)

    Eriksen, Helle Brander; Biering-Sørensen, Sofie; Lund, Najaaraq

    2014-01-01

    treatment at the time of labor (0.84 [0.70-1.00]), number of pregnancy consultations (1.03 [1.00-1.05]), maternal age (0.91 [0.84-0.98]), Apgar score (1.06 [1.03-1.10]), and infant convulsions (0.44 [0.29-0.65]) were all independent determinants of thymic index but not all were determinants of thymus....../weight index. Pathologic amniotic fluid and cesarean delivery were associated with thymus/weight index among LBW infants (0.85 [0.75-0.95] and 0.80 [0.67-0.96]) but were only borderline significant for thymic index. CONCLUSION: Exposures mainly related to stress and infections were associated with a smaller...

  12. Life events and escape in conversion disorder.

    Science.gov (United States)

    Nicholson, T R; Aybek, S; Craig, T; Harris, T; Wojcik, W; David, A S; Kanaan, R A

    2016-09-01

    Psychological models of conversion disorder (CD) traditionally assume that psychosocial stressors are identifiable around symptom onset. In the face of limited supportive evidence such models are being challenged. Forty-three motor CD patients, 28 depression patients and 28 healthy controls were assessed using the Life Events and Difficulties Schedule in the year before symptom onset. A novel 'escape' rating for events was developed to test the Freudian theory that physical symptoms of CD could provide escape from stressors, a form of 'secondary gain'. CD patients had significantly more severe life events and 'escape' events than controls. In the month before symptom onset at least one severe event was identified in 56% of CD patients - significantly more than 21% of depression patients [odds ratio (OR) 4.63, 95% confidence interval (CI) 1.56-13.70] and healthy controls (OR 5.81, 95% CI 1.86-18.2). In the same time period 53% of CD patients had at least one 'high escape' event - again significantly higher than 14% in depression patients (OR 6.90, 95% CI 2.05-23.6) and 0% in healthy controls. Previous sexual abuse was more commonly reported in CD than controls, and in one third of female patients was contextually relevant to life events at symptom onset. The majority (88%) of life events of potential aetiological relevance were not identified by routine clinical assessments. Nine per cent of CD patients had no identifiable severe life events. Evidence was found supporting the psychological model of CD, the Freudian notion of escape and the potential aetiological relevance of childhood traumas in some patients. Uncovering stressors of potential aetiological relevance requires thorough psychosocial evaluation.

  13. Cellular and biochemical actions of adrenal glucocorticoid hormones on rat thymic lymphocytes.

    OpenAIRE

    Young, D A; Voris, B P; Nicholson, M L

    1981-01-01

    The molecular, biochemical, and cellular effects of adrenal glucocorticoid hormones on thymic lymphocytes are reviewed, with emphasis on their relationship to the growth suppressive and lethal actions that occur in lymphoid tissues when glucocorticoids are administered to the whole animal. The data support the hypothesis that the hormonal inhibition of growth and development is a consequence of its ability to suppress cellular energy production, causing the cells to behave as though they were...

  14. Generation of Functional Thymic Epithelium from Human Embryonic Stem Cells that Supports Host T Cell Development

    OpenAIRE

    Parent, Audrey V.; Russ, Holger A.; Khan, Imran S.; LaFlam, Taylor N.; Metzger, Todd C.; Anderson, Mark S.; Hebrok, Matthias

    2013-01-01

    Inducing immune tolerance to prevent rejection is a key step toward successful engraftment of stem-cell-derived tissue in a clinical setting. Using human pluripotent stem cells to generate thymic epithelial cells (TECs) capable of supporting T cell development represents a promising approach to reach this goal; however, progress toward generating functional TECs has been limited. Here, we describe a robust in vitro method to direct differentiation of human embryonic stem cells (hESCs) into th...

  15. Inferior Vena Cava and Renal Vein Thrombosis Associated with Thymic Carcinoma

    Directory of Open Access Journals (Sweden)

    Vlad Teodor Berbecar

    2017-01-01

    Full Text Available Thymic tumors are rare mediastinal tumors that can present with a wide variety of symptoms. They can cause distant manifestations and are frequently associated with paraneoplastic syndromes. In our case, we describe the evolution of a 68-year-old male whose first manifestation was thrombosis of the inferior vena cava and renal veins. Thrombosis of large abdominal veins is rare, especially without being associated with any other comorbidity or risk factors.

  16. FOXN1: a master regulator gene of thymic epithelial development programme

    Directory of Open Access Journals (Sweden)

    Rosa eRomano

    2013-07-01

    Full Text Available T cell ontogeny is a sophisticated process, which takes place within the thymus through a series of well-defined discrete stages. The process requires a proper lympho-stromal interaction. In particular, cortical and medullary thymic epithelial cells (cTECs, mTECs drive T cell differentiation, education and selection processes, while the thymocyte-dependent signals allow TECs to maturate and provide an appropriate thymic microenvironment. Alterations in genes implicated in thymus organogenesis, including Tbx1, Pax1, Pax3, Pax9, Hoxa3, Eya1 and Six1, affect this well-orchestrated process, leading to disruption of thymic architecture. Of note, in both human and mice, the primordial TECs are yet unable to fully support T cell development and only after the transcriptional activation of the Forkhead-box n1 (FOXN1 gene in the thymic epithelium this essential function is acquired. FOXN1 is a master regulator in the TEC lineage specification in that it down-stream promotes transcription of genes, which, in turn, regulate TECs differentiation. In particular, FOXN1 mainly regulates TEC patterning in the fetal stage and TEC homeostasis in the postnatal thymus. An inborn null mutation in FOXN1 leads to Nude/SCID phenotype in mouse, rat and humans. In Foxn1-/- nude animals, initial formation of the primordial organ is arrested and the primordium is not colonized by hematopoietic precursors, causing a severe primary T cell immunodeficiency. In humans, the Nude/SCID phenotype is characterized by congenital alopecia of the scalp, eyebrows, and eyelashes, nail dystrophy and a severe T cell immunodeficiency, inherited as an autosomal recessive disorder. Aim of this review is to summarize all the scientific information so far available to better characterize the pivotal role of the master regulator FOXN1 transcription factor in the TEC lineage specifications and functionality.

  17. Changes in protein expression in p53 deleted spontaneous thymic lymphomas

    DEFF Research Database (Denmark)

    Honoré, Bent; Vorum, Henrik; Pedersen, Anders Elm

    2004-01-01

    with the protein expression in p53+/+ and p53-/- thymocytes. Only a minority (13 proteins) of the quantitatively changed proteins were common for the two thymic lymphoma cell lines, suggesting that the p53 deficiency mainly results in genetic dysfunctions which are individual for a given tumor. Two of the detected...... structure containing motifs of the glyoxalase-bleomycin resistance protein family (MDR) as deduced from the cDNA....

  18. Apoptosis-promoted tumorigenesis: γ-irradiation-induced thymic lymphomagenesis requires Puma-driven leukocyte death

    OpenAIRE

    Michalak, Ewa M.; Vandenberg, Cassandra J.; Delbridge, Alex R.D.; Wu, Li; Scott, Clare L.; Adams, Jerry M.; Strasser, Andreas

    2010-01-01

    Although tumor development requires impaired apoptosis, we describe a novel paradigm of apoptosis-dependent tumorigenesis. Because DNA damage triggers apoptosis through p53-mediated induction of BH3-only proteins Puma and Noxa, we explored their roles in γ-radiation-induced thymic lymphomagenesis. Surprisingly, whereas Noxa loss accelerated it, Puma loss ablated tumorigenesis. Tumor suppression by Puma deficiency reflected its protection of leukocytes from γ-irradiation-induced death, because...

  19. Effects of neonatal thymic exposure to high doses of X-irradiation

    International Nuclear Information System (INIS)

    Bains, G.S.; Sundaram, K.

    1979-01-01

    The thymic region of neonatal Swiss mice was exposed to doses varying from 1000 R to 2000 R of X-irradiation. The animals did not show any signs of wasting syndrome up to 6 months after irradiation. At this time hyperplasia of the thymus with an associated lymphocytosis was evident in irradiated animals. Antibody production to sheep red blood cells (SRBC) was not affected. However, at 12 months post-irradiation the animals showed signs of wasting disease with a progressive increase in their numbers at 18 and 24 months of age. The percentage incidence of animals with wasting disease was dose dependent. At this stage in the majority of the animals with the disease the thymus showed varying degrees of atrophy along with splenomegaly. There were no significant differences in the number of lymphocytes but the number of granulocytes showed a substantial increase. This was more evident in animals exposed to 2000 R to the thymic region. Though one observed a lowered ability to form antibodies to bovine serum albumin (BSA) with advancing age, the thymic irradiation did not affect the immune response to BSA even in animals manifesting wasting disease. An interesting observation has been the development of a severe loss of muscle power and tone in the hind limbs in a large majority of animals. (author)

  20. Mesothelioma and thymic tumors: Treatment challenges in (outside) a network setting.

    Science.gov (United States)

    Imbimbo, Martina; Maury, Jean-Michel; Garassino, Marina; Girard, Nicolas

    2018-02-02

    The management of patients with mesothelioma and thymic malignancy requires continuous multidisciplinary expertise at any step of the disease. A dramatic improvement in our knowledge has occurred in the last few years, through the development of databases, translational research programs, and clinical trials. Access to innovative strategies represents a major challenge, as there is a lack of funding for clinical research in rare cancers and their rarity precludes the design of robust clinical trials that could lead to specific approval of drugs. In this context, patient-centered initiatives, such as the establishment of dedicated networks, are warranted. International societies, such as IMIG (International Mesothelioma Interest Group) and ITMIG (International Thymic Malignancy Interest Group) provide infrastructure for global collaboration, and there are many advantages to having strong regional groups working on the same issues. There may be regional differences in risk factors, susceptibility, management and outcomes. The ability to address questions both regionally as well as globally is ideal to develop a full understanding of mesothelioma and thymic malignancies. In Europe, through the integration of national networks with EURACAN, the collaboration with academic societies and international groups, the development of networks in thoracic oncology provides multiplex integration of clinical care and research, ultimately ensuring equal access to high quality care to all patients, with the opportunity of conducting high level clinical and translational research projects. Copyright © 2018 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

  1. nab-Paclitaxel in Combination with Carboplatin for a Previously Treated Thymic Carcinoma

    Directory of Open Access Journals (Sweden)

    Go Makimoto

    2014-01-01

    Full Text Available We present the case of a 40-year-old man with previously treated thymic carcinoma, complaining of gradually worsening back pain. Computed tomography scans of the chest showed multiple pleural disseminated nodules with a pleural effusion in the right thorax. The patient was treated with carboplatin on day 1 plus nab-paclitaxel on day 1 and 8 in cycles repeated every 4 weeks. Objective tumor shrinkage was observed after 4 cycles of this regimen. In addition, the elevated serum cytokeratin 19 fragment level decreased, and the patient's back pain was relieved without any analgesics. Although he experienced grade 4 neutropenia and granulocyte colony-stimulating factor (G-CSF injection, the severity of thrombocytopenia and nonhematological toxicities such as reversible neuropathy did not exceed grade 1 during the treatment. To our knowledge, this is the first report to demonstrate the efficacy of combination chemotherapy consisting of carboplatin and nab-paclitaxel against thymic carcinoma. This case report suggests that nab-paclitaxel in combination with carboplatin can be a favorable chemotherapy regimen for advanced thymic carcinoma.

  2. HTLV-1-infected thymic epithelial cells convey the virus to CD4+ T lymphocytes.

    Science.gov (United States)

    Carvalho Barros, Luciana Rodrigues; Linhares-Lacerda, Leandra; Moreira-Ramos, Klaysa; Ribeiro-Alves, Marcelo; Machado Motta, Maria Cristina; Bou-Habib, Dumith Chequer; Savino, Wilson

    2017-12-01

    The human T-lymphotropic virus type-1 (HTLV-1) is the causative agent of adult T cell leukemia/lymphoma (ATL) and HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). CD4 + T cells are the main target of HTLV-1, but other cell types are known to be infected, including immature lymphocytes. Developing T cells undergo differentiation in the thymus, through migration and interaction with the thymic microenvironment, in particular with thymic epithelial cells (TEC) the major component of this three dimensional meshwork of non-lymphoid cells. Herein, we show that TEC express the receptors for HTLV-1 and can be infected by this virus through cell-cell contact and by cell-free virus suspensions. The expression of anti-apoptosis, chemokine and adhesion molecules genes are altered in HTLV-1-infected TEC, although gene expression of antigen presentation molecules remained unchanged. Furthermore, HTLV-1-infected TEC transmitted the virus to a CD4 + T cell line and to CD4 + T cells from healthy donors, during in vitro cellular co-cultures. Altogether, our data point to the possibility that the human thymic epithelial cells play a role in the establishment and progression of HTLV-1 infection, functioning as a reservoir and transmitting the virus to maturing CD4 + T lymphocytes, which in turn will cause disease in the periphery. Copyright © 2017. Published by Elsevier GmbH.

  3. Association between thymic function and allogeneic hematopoietic stem cell transplantation outcome: results of a pediatric study.

    Science.gov (United States)

    Saglio, Francesco; Cena, Silvia; Berger, Massimo; Quarello, Paola; Boccasavia, Viola; Ferrando, Federica; Pittana, Laura; Bruno, Benedetto; Fagioli, Franca

    2015-06-01

    Robust T cell function recovery has been shown to be crucial in determining allogeneic hematopoietic stem cell transplantation (HSCT) outcome, and there is growing evidence that the thymus plays a central role in regulating this process. We performed a long-term analysis of the role of thymic activity recovery in a population of pediatric patients undergoing allogeneic HSCT by signal joint T cell receptor excision circle (sjTREC) quantification. In this study, characterized by a long-term follow-up (median, 72 months), we found patients with higher levels of sjTRECs before transplantation had a statistically significant reduced risk of death compared with patients with lower values (relative risk, .31; 95% confidence interval, .30 to .32; P = .02), showing this different outcome was mainly related to a reduction of relapse incidence (14% versus 43%, P = .02). Unlike previous reports, we observed no correlation between sjTREC levels and lymphocyte recovery. Moreover, we confirmed that only graft-versus-host disease influenced thymic activity after transplantation. In conclusion, our results suggest an association between pretransplantation thymic activity and the long-term outcome of pediatric patients undergoing HSCT, mainly through a reduction of relapse opportunities. Copyright © 2015 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  4. Anti-Apoptotic Signature in Thymic Squamous Cell Carcinomas - Functional Relevance of Anti-Apoptotic BIRC3 Expression in the Thymic Carcinoma Cell Line 1889c.

    Science.gov (United States)

    Huang, Bei; Belharazem, Djeda; Li, Li; Kneitz, Susanne; Schnabel, Philipp A; Rieker, Ralf J; Körner, Daniel; Nix, Wilfred; Schalke, Berthold; Müller-Hermelink, Hans Konrad; Ott, German; Rosenwald, Andreas; Ströbel, Philipp; Marx, Alexander

    2013-01-01

    The molecular pathogenesis of thymomas and thymic carcinomas (TCs) is poorly understood and results of adjuvant therapy are unsatisfactory in case of metastatic disease and tumor recurrence. For these clinical settings, novel therapeutic strategies are urgently needed. Recently, limited sequencing efforts revealed that a broad spectrum of genes that play key roles in various common cancers are rarely affected in thymomas and TCs, suggesting that other oncogenic principles might be important. This made us re-analyze historic expression data obtained in a spectrum of thymomas and thymic squamous cell carcinomas (TSCCs) with a custom-made cDNA microarray. By cluster analysis, different anti-apoptotic signatures were detected in type B3 thymoma and TSCC, including overexpression of BIRC3 in TSCCs. This was confirmed by qRT-PCR in the original and an independent validation set of tumors. In contrast to several other cancer cell lines, the BIRC3-positive TSCC cell line, 1889c showed spontaneous apoptosis after BIRC3 knock-down. Targeting apoptosis genes is worth testing as therapeutic principle in TSCC.

  5. Anti-Apoptotic Signature in Thymic Squamous Cell Carcinomas – Functional Relevance of Anti-Apoptotic BIRC3 Expression in the Thymic Carcinoma Cell Line 1889c

    Science.gov (United States)

    Huang, Bei; Belharazem, Djeda; Li, Li; Kneitz, Susanne; Schnabel, Philipp A.; Rieker, Ralf J.; Körner, Daniel; Nix, Wilfred; Schalke, Berthold; Müller-Hermelink, Hans Konrad; Ott, German; Rosenwald, Andreas; Ströbel, Philipp; Marx, Alexander

    2013-01-01

    The molecular pathogenesis of thymomas and thymic carcinomas (TCs) is poorly understood and results of adjuvant therapy are unsatisfactory in case of metastatic disease and tumor recurrence. For these clinical settings, novel therapeutic strategies are urgently needed. Recently, limited sequencing efforts revealed that a broad spectrum of genes that play key roles in various common cancers are rarely affected in thymomas and TCs, suggesting that other oncogenic principles might be important. This made us re-analyze historic expression data obtained in a spectrum of thymomas and thymic squamous cell carcinomas (TSCCs) with a custom-made cDNA microarray. By cluster analysis, different anti-apoptotic signatures were detected in type B3 thymoma and TSCC, including overexpression of BIRC3 in TSCCs. This was confirmed by qRT-PCR in the original and an independent validation set of tumors. In contrast to several other cancer cell lines, the BIRC3-positive TSCC cell line, 1889c showed spontaneous apoptosis after BIRC3 knock-down. Targeting apoptosis genes is worth testing as therapeutic principle in TSCC. PMID:24427739

  6. Launch Pad Escape System Design (Human Spaceflight)

    Science.gov (United States)

    Maloney, Kelli

    2011-01-01

    A launch pad escape system for human spaceflight is one of those things that everyone hopes they will never need but is critical for every manned space program. Since men were first put into space in the early 1960s, the need for such an Emergency Escape System (EES) has become apparent. The National Aeronautics and Space Administration (NASA) has made use of various types of these EESs over the past 50 years. Early programs, like Mercury and Gemini, did not have an official launch pad escape system. Rather, they relied on a Launch Escape System (LES) of a separate solid rocket motor attached to the manned capsule that could pull the astronauts to safety in the event of an emergency. This could only occur after hatch closure at the launch pad or during the first stage of flight. A version of a LES, now called a Launch Abort System (LAS) is still used today for all manned capsule type launch vehicles. However, this system is very limited in that it can only be used after hatch closure and it is for flight crew only. In addition, the forces necessary for the LES/LAS to get the capsule away from a rocket during the first stage of flight are quite high and can cause injury to the crew. These shortcomings led to the development of a ground based EES for the flight crew and ground support personnel as well. This way, a much less dangerous mode of egress is available for any flight or ground personnel up to a few seconds before launch. The early EESs were fairly simple, gravity-powered systems to use when thing's go bad. And things can go bad very quickly and catastrophically when dealing with a flight vehicle fueled with millions of pounds of hazardous propellant. With this in mind, early EES designers saw such a passive/unpowered system as a must for last minute escapes. This and other design requirements had to be derived for an EES, and this section will take a look at the safety design requirements had to be derived for an EES, and this section will take a look at

  7. DKK1 mediated inhibition of Wnt signaling in postnatal mice leads to loss of TEC progenitors and thymic degeneration.

    Directory of Open Access Journals (Sweden)

    Masako Osada

    2010-02-01

    Full Text Available Thymic epithelial cell (TEC microenvironments are essential for the recruitment of T cell precursors from the bone marrow, as well as the subsequent expansion and selection of thymocytes resulting in a mature self-tolerant T cell repertoire. The molecular mechanisms, which control both the initial development and subsequent maintenance of these critical microenvironments, are poorly defined. Wnt signaling has been shown to be important to the development of several epithelial tissues and organs. Regulation of Wnt signaling has also been shown to impact both early thymocyte and thymic epithelial development. However, early blocks in thymic organogenesis or death of the mice have prevented analysis of a role of canonical Wnt signaling in the maintenance of TECs in the postnatal thymus.Here we demonstrate that tetracycline-regulated expression of the canonical Wnt inhibitor DKK1 in TECs localized in both the cortex and medulla of adult mice, results in rapid thymic degeneration characterized by a loss of DeltaNP63(+ Foxn1(+ and Aire(+ TECs, loss of K5K8DP TECs thought to represent or contain an immature TEC progenitor, decreased TEC proliferation and the development of cystic structures, similar to an aged thymus. Removal of DKK1 from DKK1-involuted mice results in full recovery, suggesting that canonical Wnt signaling is required for the differentiation or proliferation of TEC populations needed for maintenance of properly organized adult thymic epithelial microenvironments.Taken together, the results of this study demonstrate that canonical Wnt signaling within TECs is required for the maintenance of epithelial microenvironments in the postnatal thymus, possibly through effects on TEC progenitor/stem cell populations. Downstream targets of Wnt signaling, which are responsible for maintenance of these TEC progenitors may provide useful targets for therapies aimed at counteracting age associated thymic involution or the premature thymic

  8. Escape of atmospheres and loss of water

    International Nuclear Information System (INIS)

    Hunten, D.M.; Donahue, T.M.; Walker, J.C.G.; Kasting, J.F.

    1989-01-01

    The properties and limitations of several loss processes for atmospheric gases are presented and discussed. They include thermal loss (Jeans and hydrodynamic); nonthermal loss (all processes involve charged particles); and impact erosion, including thermal escape from a molten body heated by rapid accretion. Hydrodynamic escape, or blowoff, is of particular interest because it offers the prospect of processing large quantities of gas and enriching the remainder in heavy elements and isotopes. In a second part, the water budgets and likely evolutionary histories of Venus, Earth and Mars are assessed. Although it is tempting to associate the great D/H enrichment on Venus with loss of a large initial endowment, a steady state with juvenile water (perhaps from comets) is equally probable

  9. Biomechanics of Tetrahymena escaping from dead ends

    Science.gov (United States)

    Ishikawa, Takuji; Kikuchi, Kenji

    2017-11-01

    Behaviors of swimming microorganisms in complex environments are important in understanding cells' distribution in nature and in industries. Although cell's swimming and spreading in an infinite fluid has been intensively investigated, that in a narrow region bounded by walls is still unclear. Thus, in this study, we used Tetrahymena thermophila as a model microorganism, and experimentally investigated its behavior between flat plates with an angle. The results showed that the cells tended to escape from the narrow region, and the swimming velocity and the radius of curvature of the trajectories decreased as they swam narrower region. We then developed a computational model of swimming Tetrahymena. The results showed that the escaping behavior could be well explained by fluid mechanics. The obtained knowledge is useful in understanding cells' behaviors in complex environments, such as in porous media and in a granular matter. This research was supported by JSPS KAKENHI Grants, numbers 25000008 and 17H00853.

  10. Constraining Lyman continuum escape using Machine Learning

    Science.gov (United States)

    Giri, Sambit K.; Zackrisson, Erik; Binggeli, Christian; Pelckmans, Kristiaan; Cubo, Rubén; Mellema, Garrelt

    2018-05-01

    The James Webb Space Telescope (JWST) will observe the rest-frame ultraviolet/optical spectra of galaxies from the epoch of reionization (EoR) in unprecedented detail. While escaping into the intergalactic medium, hydrogen-ionizing (Lyman continuum; LyC) photons from the galaxies will contribute to the bluer end of the UV slope and make nebular emission lines less prominent. We present a method to constrain leakage of the LyC photons using the spectra of high redshift (z >~ 6) galaxies. We simulate JWST/NIRSpec observations of galaxies at z =6-9 by matching the fluxes of galaxies observed in the Frontier Fields observations of galaxy cluster MACS-J0416. Our method predicts the escape fraction fesc with a mean absolute error Δfesc ~ 0.14. The method also predicts the redshifts of the galaxies with an error .

  11. Measurement of the resonance escape probability

    International Nuclear Information System (INIS)

    Anthony, J.P.; Bacher, P.; Lheureux, L.; Moreau, J.; Schmitt, A.P.

    1957-01-01

    The average cadmium ratio in natural uranium rods has been measured, using equal diameter natural uranium disks. These values correlated with independent measurements of the lattice buckling, enabled us to calculate values of the resonance escape probability for the G1 reactor with one or the other of two definitions. Measurements were performed on 26 mm and 32 mm rods, giving the following values for the resonance escape probability p: 0.8976 ± 0.005 and 0.912 ± 0.006 (d. 26 mm), 0.8627 ± 0.009 and 0.884 ± 0.01 (d. 32 mm). The influence of either definition on the lattice parameters is discussed, leading to values of the effective integral. Similar experiments have been performed with thorium rods. (author) [fr

  12. Asymmetric Effects on Escape Rates of Bistable System

    International Nuclear Information System (INIS)

    Wang Canjun; Mei Dongcheng; Dai Zucheng

    2011-01-01

    The asymmetric effects on the escape rates from the stable states x ± in the bistable system are analyzed. The results indicate that the multiplicative noise and the additive noise always enhance the particle escape from stable states x ± of bistable. However, the asymmetric parameter r enhances the particle escape from stable state x + , and holds back the particle escape from stable state x - . (general)

  13. The Effects of Variable-Time Delivery of Food Items and Praise on Problem Behavior Reinforced by Escape

    Science.gov (United States)

    Lomas, Joanna E.; Fisher, Wayne W.; Kelley, Michael E.

    2010-01-01

    Prior research indicates that reinforcement of an appropriate response (e.g., compliance) can produce concomitant reductions in problem behavior reinforced by escape when problem behavior continues to produce negative reinforcement (e.g., Lalli et al., 1999). These effects may be due to a preference for positive over negative reinforcement or to…

  14. Escape and transmission probabilities in cylindrical geometry

    International Nuclear Information System (INIS)

    Bjerke, M.A.

    1980-01-01

    An improved technique for the generation of escape and transmission probabilities in cylindrical geometry was applied to the existing resonance cross section processing code ROLAIDS. The algorithm of Hwang and Toppel, [ANL-FRA-TM-118] (with modifications) was employed. The probabilities generated were found to be as accurate as those given by the method previously applied in ROLAIDS, while requiring much less computer core storage and CPU time

  15. Xenon Fractionation and Archean Hydrogen Escape

    Science.gov (United States)

    Zahnle, K. J.

    2015-01-01

    Xenon is the heaviest gas found in significant quantities in natural planetary atmospheres. It would seem the least likely to escape. Yet there is more evidence for xenon escape from Earth than for any element other than helium and perhaps neon. The most straightforward evidence is that most of the radiogenic Xe from the decay of (129)I (half-life 15.7 Myr) and (244)Pu (half-life 81 Myr) that is Earth's birthright is missing. The missing xenon is often attributed to the impact erosion of early atmospheres of Earth and its ancestors. It is obvious that if most of the radiogenic xenon were driven off by impacts, most of the rest of the atmophiles fared the same fate. The other line of evidence is in the nonradiogenic isotopes of xenon and its silent partner, krypton. Atmospheric xenon is strongly mass fractionated (at about 4% per amu) compared to any known solar system source (Figure 1). This is in stark contrast to krypton, which may not be fractionated at all: atmospheric Kr is slightly heavier than solar Kr (at about 0.5% per amu), but it is the same as in carbonaceous chondrites. Nonradiogenic xenon is also under abundant relative to krypton (the so-called "missing xenon" problem). Together these observations imply that xenon has been subject to fractionating escape and krypton not.

  16. Escape probabilities for fluorescent x-rays

    International Nuclear Information System (INIS)

    Dance, D.R.; Day, G.J.

    1985-01-01

    Computation of the energy absorption efficiency of an x-ray photon detector involves consideration of the histories of the secondary particles produced in any initial or secondary interaction which may occur within the detector. In particular, the K or higher shell fluorescent x-rays which may be emitted following a photoelectric interaction can carry away a large fraction of the energy of the incident photon, especially if this energy is just above an absorption edge. The effects of such photons cannot be ignored and a correction term, depending upon the probability that the fluorescent x-rays will escape from the detector, must be applied to the energy absorption efficiency. For detectors such as x-ray intensifying screens, it has been usual to calculate this probability by numerical integration. In this note analytic expressions are derived for the escape probability of fluorescent photons from planar detectors in terms of exponential integral functions. Rational approximations for these functions are readily available and these analytic expressions therefore facilitate the computation of photon absorption efficiencies. A table is presented which should obviate the need for calculating the escape probability for most cases of interest. (author)

  17. A Whole-Tumor Histogram Analysis of Apparent Diffusion Coefficient Maps for Differentiating Thymic Carcinoma from Lymphoma.

    Science.gov (United States)

    Zhang, Wei; Zhou, Yue; Xu, Xiao-Quan; Kong, Ling-Yan; Xu, Hai; Yu, Tong-Fu; Shi, Hai-Bin; Feng, Qing

    2018-01-01

    To assess the performance of a whole-tumor histogram analysis of apparent diffusion coefficient (ADC) maps in differentiating thymic carcinoma from lymphoma, and compare it with that of a commonly used hot-spot region-of-interest (ROI)-based ADC measurement. Diffusion weighted imaging data of 15 patients with thymic carcinoma and 13 patients with lymphoma were retrospectively collected and processed with a mono-exponential model. ADC measurements were performed by using a histogram-based and hot-spot-ROI-based approach. In the histogram-based approach, the following parameters were generated: mean ADC (ADC mean ), median ADC (ADC median ), 10th and 90th percentile of ADC (ADC 10 and ADC 90 ), kurtosis, and skewness. The difference in ADCs between thymic carcinoma and lymphoma was compared using a t test. Receiver operating characteristic analyses were conducted to determine and compare the differentiating performance of ADCs. Lymphoma demonstrated significantly lower ADC mean , ADC median , ADC 10 , ADC 90 , and hot-spot-ROI-based mean ADC than those found in thymic carcinoma (all p values histogram analysis of ADC maps can improve the differentiating performance between thymic carcinoma and lymphoma.

  18. Abnormalities of thymic stroma may contribute to immune dysregulation in murine models of leaky severe combined immunodeficiency

    Directory of Open Access Journals (Sweden)

    Francesca eRucci

    2011-05-01

    Full Text Available Lymphostromal cross-talk in the thymus is essential to allow generation of a diversified repertoire of T lymphocytes and to prevent autoimmunity by self-reactive T cells. Hypomorphic mutations in genes that control T cell development have been associated with immunodeficiency and immune dysregulation both in humans and in mice. We have studied T cell development and thymic stroma architecture and maturation in two mouse models of leaky SCID, carrying hypomorphic mutations in Rag1 and Lig4 genes. Defective T cell development was associated with abnormalities of thymic architecture that predominantly affect the thymic medulla, with reduction of the pool of mature medullary thymic epithelial cells (mTECs. While the ability of mTECs to express Aire is preserved in mutant mice, the frequency of mature mTECs expressing Aire and tissue-specific antigens (TSAs is severely reduced. Similarly, the ability of CD4+ T cells to differentiate into Foxp3+ natural regulatory T cells is preserved in Rag1 and Lig4 mutant mice, but their number is greatly reduced. These data indicate that hypomorphic defects in T cell development may cause defective lymphostromal cross-talk and impinge on thymic stromal cells maturation, and thus favor immune dysregulation.

  19. Association of murine lupus and thymic full-length endogenous retroviral expression maps to a bone marrow stem cell

    International Nuclear Information System (INIS)

    Krieg, A.M.; Gourley, M.F.; Steinberg, A.D.

    1991-01-01

    Recent studies of thymic gene expression in murine lupus have demonstrated 8.4-kb (full-length size) modified polytropic (Mpmv) endogenous retroviral RNA. In contrast, normal control mouse strains do not produce detectable amounts of such RNA in their thymuses. Prior studies have attributed a defect in experimental tolerance in murine lupus to a bone marrow stem cell rather than to the thymic epithelium; in contrast, infectious retroviral expression has been associated with the thymic epithelium, rather than with the bone marrow stem cell. The present study was designed to determine whether the abnormal Mpmv expression associated with murine lupus mapped to thymic epithelium or to a marrow precursor. Lethally irradiated control and lupus-prone mice were reconstituted with T cell depleted bone marrow; one month later their thymuses were studied for endogenous retroviral RNA and protein expression. Recipients of bone marrow from nonautoimmune donors expressed neither 8.4-kb Mpmv RNA nor surface MCF gp70 in their thymuses. In contrast, recipients of bone marrow from autoimmune NZB or BXSB donors expressed thymic 8.4-kb Mpmv RNA and mink cell focus-forming gp70. These studies demonstrate that lupus-associated 8.4-kb Mpmv endogenous retroviral expression is determined by bone marrow stem cells

  20. Risks incurred by hydrogen escaping from containers and conduits

    Energy Technology Data Exchange (ETDEWEB)

    Swain, M.R.; Grilliot, E.S. [Univ. of Miami, Coral Gables, FL (United States); Swain, M.N. [Analytical Technologies, Inc., Miami, FL (United States)

    1998-08-01

    This paper is a discussion of a method for hydrogen leak classification. Leaks are classified as; gas escapes into enclosed spaces, gas escapes into partially enclosed spaces (vented), and gas escapes into unenclosed spaces. Each of the three enclosure classifications is further divided into two subclasses; total volume of hydrogen escaped and flow rate of escaping hydrogen. A method to aid in risk assessment determination in partially enclosed spaces is proposed and verified for several enclosure geometries. Examples are discussed for additional enclosure geometries.

  1. Pre-T Cell Receptors (Pre-TCRs) Leverage Vβ Complementarity Determining Regions (CDRs) and Hydrophobic Patch in Mechanosensing Thymic Self-ligands.

    Science.gov (United States)

    Das, Dibyendu Kumar; Mallis, Robert J; Duke-Cohan, Jonathan S; Hussey, Rebecca E; Tetteh, Paul W; Hilton, Mark; Wagner, Gerhard; Lang, Matthew J; Reinherz, Ellis L

    2016-12-02

    The pre-T cell receptor (pre-TCR) is a pTα-β heterodimer functioning in early αβ T cell development. Although once thought to be ligand-autonomous, recent studies show that pre-TCRs participate in thymic repertoire formation through recognition of peptides bound to major histocompatibility molecules (pMHC). Using optical tweezers, we probe pre-TCR bonding with pMHC at the single molecule level. Like the αβTCR, the pre-TCR is a mechanosensor undergoing force-based structural transitions that dynamically enhance bond lifetimes and exploiting allosteric control regulated via the Cβ FG loop region. The pre-TCR structural transitions exhibit greater reversibility than TCRαβ and ordered force-bond lifetime curves. Higher piconewton force requires binding through both complementarity determining region loops and hydrophobic Vβ patch apposition. This patch functions in the pre-TCR as a surrogate Vα domain, fostering ligand promiscuity to favor development of β chains with self-reactivity but is occluded by α subunit replacement of pTα upon αβTCR formation. At the double negative 3 thymocyte stage where the pre-TCR is first expressed, pre-TCR interaction with self-pMHC ligands imparts growth and survival advantages as revealed in thymic stromal cultures, imprinting fundamental self-reactivity in the T cell repertoire. Collectively, our data imply the existence of sequential mechanosensor αβTCR repertoire tuning via the pre-TCR. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. RasGRP1, but not RasGRP3, is required for efficient thymic β-selection and ERK activation downstream of CXCR4.

    Directory of Open Access Journals (Sweden)

    Dominic P Golec

    Full Text Available T cell development is a highly dynamic process that is driven by interactions between developing thymocytes and the thymic microenvironment. Upon entering the thymus, the earliest thymic progenitors, called CD4(-CD8(- 'double negative' (DN thymocytes, pass through a checkpoint termed "β-selection" before maturing into CD4(+CD8(+ 'double positive' (DP thymocytes. β-selection is an important developmental checkpoint during thymopoiesis where developing DN thymocytes that successfully express the pre-T cell receptor (TCR undergo extensive proliferation and differentiation towards the DP stage. Signals transduced through the pre-TCR, chemokine receptor CXCR4 and Notch are thought to drive β-selection. Additionally, it has long been known that ERK is activated during β-selection; however the pathways regulating ERK activation remain unknown. Here, we performed a detailed analysis of the β-selection events in mice lacking RasGRP1, RasGRP3 and RasGRP1 and 3. We report that RasGRP1 KO and RasGRP1/3 DKO deficient thymi show a partial developmental block at the early DN3 stage of development. Furthermore, DN3 thymocytes from RasGRP1 and RasGRP1/3 double knock-out thymi show significantly reduced proliferation, despite expression of the TCRβ chain. As a result of impaired β-selection, the pool of TCRβ(+ DN4 is significantly diminished, resulting in inefficient DN to DP development. Also, we report that RasGRP1 is required for ERK activation downstream of CXCR4 signaling, which we hypothesize represents a potential mechanism of RasGRP1 regulation of β-selection. Our results demonstrate that RasGRP1 is an important regulator of proliferation and differentiation at the β-selection checkpoint and functions downstream of CXCR4 to activate the Ras/MAPK pathway.

  3. Increased cell division but not thymic dysfunction rapidly affects the T-cell receptor excision circle content of the naive T cell population in HIV-1 infection

    NARCIS (Netherlands)

    Hazenberg, Mette D.; Borleffs, J.C.C.; Otto, S.A.; Cohen Stuart, J.W.T. (James Willem Theodoor); Verschuren, M.C.M. (Martie); Boucher, C.A.B.; Coutinho, R.A.; Lange, Joep M.A.; Rinke de Wit, T.F. (Tobias); Tsegaye, A. (Aster); Dongen, J.J.M. (Jaques) van; Hamann, D. (Dörte); Boer, R.J. de; Miedema, F.

    2000-01-01

    Recent thymic emigrants can be identified by T cell receptor excision circles (TRECs) formed during T-cell receptor rearrangement. Decreasing numbers of TRECs have been observed with aging and in human immunodeficiency virus (HIV)-1 infected individuals, suggesting for thymic impairment. Here,

  4. The cost of the sword: escape performance in male swordtails.

    Directory of Open Access Journals (Sweden)

    Alex Baumgartner

    2011-01-01

    Full Text Available The handicap theory of sexual selection posits that male display traits that are favored in mate choice come at a significant cost to performance. We tested one facet of this hypothesis in the green swordtail (Xiphophorus helleri. In this species, the lower ray of male caudal fin is extended into a 'sword', which serves to attract potential mates. However, bearing a long sword may increase drag and thus compromise a male's ability to swim effectively. We tested escape performance in this species by eliciting C-start escape responses, an instinctive escape behavior, in males with various sword lengths. We then removed males' swords and retested escape performance. We found no relationship between escape performance and sword length and no effect of sword removal on escape performance. While having a large sword may attract a predator's attention, our results suggest that sword size does not compromise a male's escape performance.

  5. Strange culinary encounters::stranger fetichism in "Jamie's Italian escape" and "Gordon's great escape"

    OpenAIRE

    Leer, Jonatan; Kjær, Katrine Meldgaard

    2015-01-01

    In this article, we examine the ways in which the encountering of 'other' food cultures is played out in the two travelogue cooking shows Gordon's Great Escape and Jamie's Italian Escape. We investigate how the two protagonist chefs Jamie Oliver and Gordon Ramsay imagine, meet and evaluate the ‘other’ food cultures in these programs, paying special attention to how the encounter with the local Indian and Italian is imagined to be a gateway to an authentic and/or primitive experience. Our main...

  6. Room escape at class: Escape games activities to facilitate the motivation and learning in computer science

    Directory of Open Access Journals (Sweden)

    Carlos Borrego

    2017-06-01

    Full Text Available Real-life room-escape games are ludic activities in which participants enter a room in order to get out of it only after solving some riddles. In this paper, we explain a Room Escape teaching experience developed in the Engineering School at Universitat Autònoma de Barcelona. The goal of this activity is to increase student’s motivation and to improve their learning on two courses of the second year in the Computer Engineering degree: Computer Networksand Information and Security.

  7. Room escape at class: escape games activities to facilitate the motivation and learning in computer science

    OpenAIRE

    Borrego, Carlos; Fernández, Cristina; Blanes, Ian; Robles, Sergi

    2017-01-01

    Real-life room-escape games are ludic activities in which participants enter a room in order to get out of it only after solving some riddles. In this paper, we explain a Room Escape teaching experience developed in the Engineering School at Universitat Autònoma de Barcelona. The goal of this activity is to increase student’s motivation and to improve their learning on two courses of the second year in the Computer Engineering degree: Computer Networksand Information and Security Peer Revi...

  8. How nonuniform contact profiles of T cell receptors modulate thymic selection outcomes

    Science.gov (United States)

    Chen, Hanrong; Chakraborty, Arup K.; Kardar, Mehran

    2018-03-01

    T cell receptors (TCRs) bind foreign or self-peptides attached to major histocompatibility complex (MHC) molecules, and the strength of this interaction determines T cell activation. Optimizing the ability of T cells to recognize a diversity of foreign peptides yet be tolerant of self-peptides is crucial for the adaptive immune system to properly function. This is achieved by selection of T cells in the thymus, where immature T cells expressing unique, stochastically generated TCRs interact with a large number of self-peptide-MHC; if a TCR does not bind strongly enough to any self-peptide-MHC, or too strongly with at least one self-peptide-MHC, the T cell dies. Past theoretical work cast thymic selection as an extreme value problem and characterized the statistical enrichment or depletion of amino acids in the postselection TCR repertoire, showing how T cells are selected to be able to specifically recognize peptides derived from diverse pathogens yet have limited self-reactivity. Here, we investigate how the diversity of the postselection TCR repertoire is modified when TCRs make nonuniform contacts with peptide-MHC. Specifically, we were motivated by recent experiments showing that amino acids at certain positions of a TCR sequence have large effects on thymic selection outcomes, and crystal structure data that reveal a nonuniform contact profile between a TCR and its peptide-MHC ligand. Using a representative TCR contact profile as an illustration, we show via simulations that the statistical enrichment or depletion of amino acids now varies by position according to the contact profile, and, importantly, it depends on the implementation of nonuniform contacts during thymic selection. We explain these nontrivial results analytically. Our study has implications for understanding the selection forces that shape the functionality of the postselection TCR repertoire.

  9. Plxnd1 expression in thymocytes regulates their intrathymic migration while that in thymic endothelium impacts medullary topology

    Directory of Open Access Journals (Sweden)

    Young Il Choi

    2013-11-01

    Full Text Available An important role for plexinD1 in thymic development is inferred from studies of germline Plxnd1 knockout (KO mice where mislocalized CD69+ thymocytes as well as ectopic thymic subcapsular medullary structures were observed. Given embryonic lethality of the Plxnd1-/- genotype, fetal liver transplantation was employed in these prior analyses. Such embryonic hematopoietic reconstitution may have transferred Plxnd1 KO endothelial and/or epithelial stem cells in addition to Plxnd1 KO lymphoid progenitors, thereby contributing to that phenotype. Here we use Plxnd1flox/flox mice crossed to pLck-Cre, pKeratin14-Cre or pTek-Cre transgenic animals to create cell-type specific conditional knockout (CKO lines involving thymocytes (D1ThyCKO, thymic epithelium (D1EpCKO and thymic endothelium (D1EnCKO, respectively. These CKOs allowed us to directly assess the role of plexinD1 in each lineage. Loss of plexinD1 expression on double positive (DP thymocytes leads to their aberrant migration and cortical retention after TCR-mediated positive selection. In contrast, ectopic medulla formation is a consequence of loss of plexinD1 expression on endothelial cells, in turn linked to dysregulation of thymic angiogenesis. D1EpCKO thymi manifest neither abnormality. Collectively, our findings underscore the non-redundant roles for plexinD1 on thymocytes and endothelium, including the dynamic nature of medulla formation resulting from crosstalk between these thymic cellular components.

  10. A thymic neuroendocrine tumour in a young female: a rare cause of relapsing and remitting Cushing's syndrome.

    Science.gov (United States)

    Trott, M J; Farah, G; Stokes, V J; Wang, L M; Grossman, A B

    2016-01-01

    We present a case of a young female patient with a rare cause of relapsing and remitting Cushing's syndrome due to ectopic ACTH secretion from a thymic neuroendocrine tumour. A 34-year-old female presented with a constellation of symptoms of Cushing's syndrome, including facial swelling, muscle weakness and cognitive impairment. We use the terms 'relapsing and remitting' in this case report, given the unpredictable time course of symptoms, which led to a delay of 2 years before the correct diagnosis of hypercortisolaemia. Diagnostic workup confirmed ectopic ACTH secretion, and a thymic mass was seen on mediastinal imaging. The patient subsequently underwent thymectomy with complete resolution of her symptoms. Several case series have documented the association of Cushing's syndrome with thymic neuroendocrine tumours (NETs), although to our knowledge there are a few published cases of patients with relapsing and remitting symptoms. This case is also notable for the absence of features of the MEN-1 syndrome, along with the female gender of our patient and her history of non-smoking. Ectopic corticotrophin (ACTH) secretion should always be considered in the diagnostic workup of young patients with Cushing's syndromeThere is a small but growing body of literature describing the correlation between ectopic ACTH secretion and thymic neuroendocrine tumours (NETs)The possibility of a MEN-1 syndrome should be considered in all patients with thymic NETs, and we note the observational association with male gender and cigarette smoking in this cohortAn exception to these associations is the finding of relatively high incidence of thymic NETs among female non-smoking MEN-1 patients in the Japanese compared with Western populationsThe relapsing and remitting course of our patient's symptoms is noteworthy, given the paucity of this finding among other published cases.

  11. Arduino adventures escape from Gemini station

    CERN Document Server

    Kelly, James Floyd

    2013-01-01

    Arduino Adventures: Escape from Gemini Station provides a fun introduction to the Arduino microcontroller by putting you (the reader) into the action of a science fiction adventure story.  You'll find yourself following along as Cade and Elle explore Gemini Station-an orbiting museum dedicated to preserving and sharing technology throughout the centuries. Trouble ensues. The station is evacuated, including Cade and Elle's class that was visiting the station on a field trip. Cade and Elle don't make it aboard their shuttle and are trapped on the station along with a friendly artificial intellig

  12. S1P lyase in thymic perivascular spaces promotes egress of mature thymocytes via up-regulation of S1P receptor 1.

    Science.gov (United States)

    Maeda, Yasuhiro; Yagi, Hideki; Takemoto, Kana; Utsumi, Hiroyuki; Fukunari, Atsushi; Sugahara, Kunio; Masuko, Takashi; Chiba, Kenji

    2014-05-01

    Sphingosine 1-phosphate (S1P) and S1P receptor 1 (S1P1) play an important role in the egress of mature CD4 or CD8 single-positive (SP) thymocytes from the thymus. Fingolimod hydrochloride (FTY720), an S1P1 functional antagonist, induced significant accumulation of CD62L(high)CD69(low) mature SP thymocytes in the thymic medulla. Immunohistochemical staining using anti-S1P1 antibody revealed that S1P1 is predominantly expressed on thymocytes in the thymic medulla and is strongly down-regulated even at 3h after FTY720 administration. 2-Acetyl-4-tetrahydroxybutylimidazole (THI), an S1P lyase inhibitor, also induced accumulation of mature SP thymocytes in the thymic medulla with an enlargement of the perivascular spaces (PVS). At 6h after THI administration, S1P1-expressing thymocytes reduced partially as if to form clusters and hardly existed in the proximity of CD31-expressing blood vessels in the thymic medulla, suggesting S1P lyase expression in the cells constructing thymic medullary PVS. To determine the cells expressing S1P lyase in the thymus, we newly established a mAb (YK19-2) specific for mouse S1P lyase. Immunohistochemical staining with YK19-2 revealed that S1P lyase is predominantly expressed in non-lymphoid thymic stromal cells in the thymic medulla. In the thymic medullary PVS, S1P lyase was expressed in ER-TR7-positive cells (reticular fibroblasts and pericytes) and CD31-positive vascular endothelial cells. Our findings suggest that S1P lyase expressed in the thymic medullary PVS keeps the tissue S1P concentration low around the vessels and promotes thymic egress via up-regulation of S1P1.

  13. Thymic involvement in immune recovery during antiretroviral treatment of HIV infection in adults; comparison of CT and sonographic findings

    DEFF Research Database (Denmark)

    Kolte, Lilian; Strandberg, Charlotte; Dreves, Anne-Mette

    2002-01-01

    In adult HIV-infected patients, thymic size evaluated from CT scans seems to be important to the degree of immune reconstitution obtainable during treatment with highly active antiretroviral therapy (HAART). To examine whether ultrasound is as reliable as CT for estimating thymic size...... and predicting immune recovery, CT and ultrasound scans were performed in 25 adult HIV-infected patients and 10 controls. CD4 counts and naive CD4 counts were measured in order to determine immune reconstitution. Furthermore, the CD4+ T-cell receptor excision circle (TREC) frequency and T-cell receptor (TCR...

  14. Mars atmospheric escape and evolution; interaction with the solar wind

    Science.gov (United States)

    Chassefière, Eric; Leblanc, François

    2004-09-01

    This tutorial deals with the question of atmospheric escape on Mars. After a brief introduction describing the general context of Mars escape studies, we will present in Section 2 a simplified theory of thermal escape, of both Jeans and hydrodynamic types. The phenomenon of hydrodynamic escape, still hypothetical and not proved to have ever existed on terrestrial planets, will be treated with the help of two well known examples: (i) the isotopic fractionation of xenon in Mars and Earth atmospheres, (ii) the paradox of missing oxygen in Venus atmosphere. In Section 3, a simplified approach of non-thermal escape will be developed, treating in a specific way the different kinds of escape (photochemical escape, ion sputtering, ion escape and ionospheric outflow). As a matter of illustration, some calculations of the relative contributions of these mechanisms, and of their time evolutions, will be given, and the magnitude of the total amount of atmosphere lost by non-thermal escape will be estimated. Section 4 will present the state of knowledge concerning the constraints derived from Mars isotopic geochemistry in terms of past escape and evolution. Finally, a few conclusions, which are more interrogations, will be proposed.

  15. Molecular Dications in Planetary Atmospheric Escape

    Directory of Open Access Journals (Sweden)

    Stefano Falcinelli

    2016-08-01

    Full Text Available Fundamental properties of multiply charged molecular ions, such as energetics, structure, stability, lifetime and fragmentation dynamics, are relevant to understand and model the behavior of gaseous plasmas as well as ionosphere and astrophysical environments. Experimental determinations of the Kinetic Energy Released (KER for ions originating from dissociations reactions, induced by Coulomb explosion of doubly charged molecular ions (molecular dications produced by double photoionization of CO2, N2O and C2H2 molecules of interest in planetary atmospheres, are reported. The KER measurement as a function of the ultraviolet (UV photon energy in the range of 28–65 eV was extracted from the electron-ion-ion coincidence spectra obtained by using tunable synchrotron radiation coupled with ion imaging techniques at the ELETTRA Synchrotron Light Laboratory Trieste, Italy. These experiments, coupled with a computational analysis based on a Monte Carlo trajectory simulation, allow assessing the probability of escape for simple ionic species in the upper atmosphere of Mars, Venus and Titan. The measured KER in the case of H+, C+, CH+, CH2+, N+, O+, CO+, N2+ and NO+ fragment ions range between 1.0 and 5.5 eV, being large enough to allow these ionic species to participate in the atmospheric escape from such planets into space. In the case of Mars, we suggest a possible explanation for the observed behavior of the O+ and CO22+ ion density profiles.

  16. Escape from viscosity : the kinematics and hydrodynamics of copepod foraging and escape swimming

    NARCIS (Netherlands)

    van Duren, LA; Videler, JJ

    Feeding and escape swimming in adult females of the calanoid copepod. Temora lopgicornis Muller were investigated and compared. Swimming velocities were calculated using a 3-D filming setup., Foraging velocities ranged between 2 and 6 min s(-1), while maximum velocities of up to 80 mm s(-1) were

  17. Titan's hydrodynamically escaping atmosphere: Escape rates and the structure of the exobase region

    Science.gov (United States)

    Strobel, Darrell F.

    2009-08-01

    In Strobel [Strobel, D.F., 2008. Icarus, 193, 588-594] a mass loss rate from Titan's upper atmosphere, ˜4.5×10 amus, was calculated for a single constituent, N 2 atmosphere by hydrodynamic escape as a high density, slow outward expansion driven principally by solar UV heating due to CH 4 absorption. It was estimated, but not proven, that the hydrodynamic mass loss is essentially CH 4 and H 2 escape. Here the individual conservation of momentum equations for the three major components of the upper atmosphere (N 2, CH 4, H 2) are solved in the low Mach number limit and compared with Cassini Ion Neutral Mass Spectrometer (INMS) measurements to demonstrate that light gases (CH 4, H 2) preferentially escape over the heavy gas (N 2). The lightest gas (H 2) escapes with a flux 99% of its limiting flux, whereas CH 4 is restricted to ⩾75% of its limiting flux because there is insufficient solar power to support escape at the limiting rate. The respective calculated H 2 and CH 4 escape rates are 9.2×10 and 1.7×10 s, for a total of ˜4.6×10 amus. From the calculated densities, mean free paths of N 2, CH 4, H 2, and macroscopic length scales, an extended region above the classic exobase is inferred where frequent collisions are still occurring and thermal heat conduction can deliver power to lift the escaping gas out of the gravitational potential well. In this region rapid acceleration of CH 4 outflow occurs. With the thermal structure of Titan's thermosphere inferred from INMS data by Müller-Wodarg et al. [Müller-Wodarg, I.C.F., Yelle, R.V., Cui, J., Waite Jr., J.H., 2008. J. Geophys. Res. 113, doi:10.1029/2007JE003033. E10005], in combination with calculated temperature profiles that include sputter induced plasma heating at the exobase, it is concluded that on average that the integrated, globally average, orbit-averaged, plasma heating rate during the Cassini epoch does not exceed ˜5×10 eVcms ( ˜0.0008 ergcms).

  18. Thymic lesions and myasthenia gravis. Diagnosis based on mediastinal imaging and pathological findings

    International Nuclear Information System (INIS)

    Pirronti, T.; Rinaldi, P.; Marano, P.; Batocchi, A.P.; Evoli, A.; Di Schino, C.

    2002-01-01

    Purpose: To achieve a better understanding of the role of CT and MR imaging in the study of the mediastinum in patients with myasthenia gravis (MG). Material and Methods: Mediastinal CT and MR findings were correlated with the histopathological results in 104 thymectomized MG patients. Results: CT was performed in 104 patients; in 11 of them, MR was also carried out. 44 patients had hyperplasia at histology. On CT, thymic hyperplasia was confirmed in 16 cases, thymoma was diagnosed in 10 and a normal thymus in 18 (sensitivity 36%, specificity 95%). Of 52 patients with thymoma at histology, CT showed thymoma in 46, hyperplasia in 1, and normal thymus in 5. CT showed 88.5% sensitivity and 77% specificity for thymoma. In 10 patients with invasive thymoma, CT was indiscriminate, while invasiveness was detected in 7 cases at MR (70% sensitivity) and at CT in 1 case. Both CT and MR detected tumor recurrence in 5 cases, but the exact localization and degree of invasion were best defined by MR. Conclusion: In MG patients CT is a sensitive, specific and efficient modality for detecting thymoma, but is less so for detecting thymic hyperplasia. MR was shown to be accurate in detecting invasive thymoma both preoperatively and in postoperative follow-up

  19. Complicated biallelic inactivation of Pten in radiation-induced mouse thymic lymphomas

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Yu [Department of Biology, Graduate School of Science, Chiba University, Yayoicho, Inage-ku, Chiba 263-8522 (Japan); Experimental Radiobiology for Children' s Health Research Group, Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Takabatake, Takashi; Kakinuma, Shizuko; Amasaki, Yoshiko; Nishimura, Mayumi; Imaoka, Tatsuhiko; Yamauchi, Kazumi; Shang, Yi [Experimental Radiobiology for Children' s Health Research Group, Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Miyoshi-Imamura, Tomoko [Experimental Radiobiology for Children' s Health Research Group, Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Genetic Counseling Program, Graduate School of Humanities and Sciences, Ochanomizu University, 2-1-1 Otsuka, Bunkyou-ku, Tokyo 112-8610 (Japan); Nogawa, Hiroyuki [Department of Biology, Graduate School of Science, Chiba University, Yayoicho, Inage-ku, Chiba 263-8522 (Japan); Kobayashi, Yoshiro [Department of Biomolecular Science, Faculty of Science, Toho University, Miyama 2-2-1, Funabashi, Chiba 274-8510 (Japan); Shimada, Yoshiya, E-mail: y_shimad@nirsgo.jp [Experimental Radiobiology for Children' s Health Research Group, Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan)

    2010-04-01

    Inactivation of the phosphatase and tensin homolog gene (Pten) occurs via multiple tissue-dependent mechanisms including epigenetic silencing, point mutations, insertions, and deletions. Although frequent loss of heterozygosity around the Pten locus and plausible involvement of epigenetic silencing have been reported in radiation-induced thymic lymphomas, the proportion of lymphomas with inactivated Pten and the spectrum of causal aberrations have not been extensively characterized. Here, we assessed the mode of Pten inactivation by comprehensive analysis of the expression and alteration of Pten in 23 radiation-induced thymic lymphomas developed in B6C3F1 mice. We found no evidence for methylation-associated silencing of Pten; rather, complex structural abnormalities comprised of missense and nonsense mutations, 1- and 3-bp insertions, and focal deletions were identified in 8 of 23 lymphomas (35%). Sequencing of deletion breakpoints suggested that aberrant V(D)J recombination and microhomology-mediated rearrangement were responsible for the focal deletions. Seven of the 8 lymphomas had biallelic alterations, and 4 of them did not express Pten protein. These Pten aberrations coincided with downstream Akt phosphorylation. In conclusion, we demonstrate that Pten inactivation is frequently biallelic and is caused by a variety of structural abnormalities (rather than by epigenetic silencing) and is involved in radiation-induced lymphomagenesis.

  20. Postoperative Radiation Therapy for Non-Small Cell Lung Cancer and Thymic Malignancies

    International Nuclear Information System (INIS)

    Gomez, Daniel R.; Komaki, Ritsuko

    2012-01-01

    For many thoracic malignancies, surgery, when feasible, is the preferred upfront modality for local control. However, adjuvant radiation plays an important role in minimizing the risk of locoregional recurrence. Tumors in the thoracic category include certain subgroups of non-small cell lung cancer (NSCLC) as well as thymic malignancies. The indications, radiation doses, and treatment fields vary amongst subtypes of thoracic tumors, as does the level of data supporting the use of radiation. For example, in the setting of NSCLC, postoperative radiation is typically reserved for close/positive margins or N2/N3 disease, although such diseases as superior sulcus tumors present unique cases in which the role of neoadjuvant vs. adjuvant treatment is still being elucidated. In contrast, for thymic malignancies, postoperative radiation therapy is often used for initially resected Masaoka stage III or higher disease, with its use for stage II disease remaining controversial. This review provides an overview of postoperative radiation therapy for thoracic tumors, with a separate focus on superior sulcus tumors and thymoma, including a discussion of acceptable radiation approaches and an assessment of the current controversies involved in its use

  1. Homeostatic properties and phenotypic maturation of murine CD4+ pre-thymic emigrants in the thymus.

    Directory of Open Access Journals (Sweden)

    Jie Dong

    Full Text Available After a tightly regulated developmental program in the thymus, "mature" single positive (SP thymocytes leave the thymus and enter the periphery. These newly arrived recent thymic emigrants (RTEs are phenotypically and functionally immature, and will complete a dynamic maturation in the peripheral lymphoid organs before being licensed to be resident naïve T cells. To study the early events occurring in the RTE maturation process, we identified the phenotype of CD4(+ pre-RTEs, a population of CD4(+ SP thymocytes that have acquired the thymus egress capability. Compared to peripheral naïve T cells, CD4(+ pre-RTEs displayed superior survival capability in lymphoreplete mice and faster proliferation under lymphopenic condition. The differences in Bcl2/Bim expression and/or heightened IL-7 signaling pathway may account for the pre-RTEs' better responsiveness to homeostatic signals. Qa2, the expression of which indicates the phenotypic maturation of SPs and RTEs, was found to be upregulated in CD4(+ pre-RTEs in thymic perivascular space. Migratory dendritic cells that surround this region contribute to Qa2 expression in pre-RTEs. The dendritic cell-driven Qa2 induction of CD4(+ pre-RTEs is independent of MHC class II and Aire molecules.

  2. Synergistic action of radiation and chemical carcinogen in induction of thymic lymphoma in mice

    International Nuclear Information System (INIS)

    Kajitani, Takashi; Kamiya, Kenji; Seyama, Toshio; Ito, Takaaki; Yokoro, Kenjiro

    1980-01-01

    Young adult C57BL/6 female mice were used to study the induction of leukemia by a combined treatment of x-rays and N-nitrosoethylurea (NEU). Administration of NEU after x-ray irradiation induced the leukemia in 100% with shortening latent period, which indicated that the combined treatment enhanced the leukemia induction. Thymic localized X-irradiation decreased the leukemia induction ratio from 100 to 55% and prolonged the latent period from 86 days to 128 days, compared with the whole body irradiation. For whole body irradiation, thymus weights, cell counts, rates of DNA-synthesizing cells, and rates, of mitotic index were decreased markedly after irradiation. For thymus weights and cell counts minimum values were observed after 3 days, and recovered by 10 days. DNA-synthesizing cells and the rates of mitotic index began to increase from the minimum value at the first day to the maximum value at the 5th day after irradiation. By thymic localized irradiation, no marked damage nor recovering process could be followed. It was suggested that the administration of NEU after irradiation, especially, to the young recovering cells with high potential for proliferation derived the high induction rate of leukemia. (Nakanishi, T.)

  3. Hematological alterations and thymic function in newborns of HIV-infected mothers receiving antiretroviral drugs.

    Science.gov (United States)

    Wongnoi, Rotjanee; Penvieng, Nawaporn; Singboottra, Panthong; Kingkeow, Doungnapa; Oberdorfer, Peninnah; Sirivatanapa, Pannee; Pornprasert, Sakorn

    2013-06-08

    To investigate the effects of antiretroviral (ARV) drugs on hematological parameters and thymic function in HIV-uninfected newborns of HIV-infected mothers. Cross sectional study. Chiang-Mai University Hospital, Chiang-Mai, Thailand. 49 HIV-uninfected and 26 HIV-infected pregnancies. Cord blood samples of newborns from HIV-uninfected and HIV-infected mothers were collected. Hematological parameters were measured using automatic blood cell count. T-cell receptor excision circles (TRECs) levels in cord blood mononuclear cells (CBMCs), CD4+ and CD8+ T-cells were quantified using real-time PCR.. Hemotological parameters and thymic function. Newborn of HIV-infected mother tended to have lower mean levels of hemoglobin than those of HIV-uninfected mother (137 ±22 vs 146 ±17 g/L, P = 0.05). Furthermore, mean of red blood cell (RBC) counts and hematocrit and median of TRECs in CD4+ T-cells in the newborns of the former were significantly lower than those of the latter [3.6 ±0.7 vs 4.8 ±0.6 x 1012 cells/L, P cells) in HIV-uninfected newborns of HIV-infected mothers.

  4. S1P Lyase Regulation of Thymic Egress and Oncogenic Inflammatory Signaling

    Science.gov (United States)

    Kumar, Ashok; Zamora-Pineda, Jesus; Degagné, Emilie

    2017-01-01

    Sphingosine-1-phosphate (S1P) is a potent lipid signaling molecule that regulates pleiotropic biological functions including cell migration, survival, angiogenesis, immune cell trafficking, inflammation, and carcinogenesis. It acts as a ligand for a family of cell surface receptors. S1P concentrations are high in blood and lymph but low in tissues, especially the thymus and lymphoid organs. S1P chemotactic gradients are essential for lymphocyte egress and other aspects of physiological cell trafficking. S1P is irreversibly degraded by S1P lyase (SPL). SPL regulates lymphocyte trafficking, inflammation and other physiological and pathological processes. For example, SPL located in thymic dendritic cells acts as a metabolic gatekeeper that controls the normal egress of mature T lymphocytes from the thymus into the circulation, whereas SPL deficiency in gut epithelial cells promotes colitis and colitis-associated carcinogenesis (CAC). Recently, we identified a complex syndrome comprised of nephrosis, adrenal insufficiency, and immunological defects caused by inherited mutations in human SGPL1, the gene encoding SPL. In the present article, we review current evidence supporting the role of SPL in thymic egress, inflammation, and cancer. Lastly, we summarize recent progress in understanding other SPL functions, its role in inherited disease, and SPL targeting for therapeutic purposes. PMID:29333002

  5. Thymic lesions and myasthenia gravis. Diagnosis based on mediastinal imaging and pathological findings

    Energy Technology Data Exchange (ETDEWEB)

    Pirronti, T.; Rinaldi, P.; Marano, P. [Univ. Cattolica del S. Cuore, Roma (Italy). Inst. of Radiology; Batocchi, A.P.; Evoli, A.; Di Schino, C. [Univ. Cattolica del S. Cuore, Roma (Italy). Inst. of Neurology

    2002-07-01

    Purpose: To achieve a better understanding of the role of CT and MR imaging in the study of the mediastinum in patients with myasthenia gravis (MG). Material and Methods: Mediastinal CT and MR findings were correlated with the histopathological results in 104 thymectomized MG patients. Results: CT was performed in 104 patients; in 11 of them, MR was also carried out. 44 patients had hyperplasia at histology. On CT, thymic hyperplasia was confirmed in 16 cases, thymoma was diagnosed in 10 and a normal thymus in 18 (sensitivity 36%, specificity 95%). Of 52 patients with thymoma at histology, CT showed thymoma in 46, hyperplasia in 1, and normal thymus in 5. CT showed 88.5% sensitivity and 77% specificity for thymoma. In 10 patients with invasive thymoma, CT was indiscriminate, while invasiveness was detected in 7 cases at MR (70% sensitivity) and at CT in 1 case. Both CT and MR detected tumor recurrence in 5 cases, but the exact localization and degree of invasion were best defined by MR. Conclusion: In MG patients CT is a sensitive, specific and efficient modality for detecting thymoma, but is less so for detecting thymic hyperplasia. MR was shown to be accurate in detecting invasive thymoma both preoperatively and in postoperative follow-up.

  6. S1P Lyase Regulation of Thymic Egress and Oncogenic Inflammatory Signaling

    Directory of Open Access Journals (Sweden)

    Ashok Kumar

    2017-01-01

    Full Text Available Sphingosine-1-phosphate (S1P is a potent lipid signaling molecule that regulates pleiotropic biological functions including cell migration, survival, angiogenesis, immune cell trafficking, inflammation, and carcinogenesis. It acts as a ligand for a family of cell surface receptors. S1P concentrations are high in blood and lymph but low in tissues, especially the thymus and lymphoid organs. S1P chemotactic gradients are essential for lymphocyte egress and other aspects of physiological cell trafficking. S1P is irreversibly degraded by S1P lyase (SPL. SPL regulates lymphocyte trafficking, inflammation and other physiological and pathological processes. For example, SPL located in thymic dendritic cells acts as a metabolic gatekeeper that controls the normal egress of mature T lymphocytes from the thymus into the circulation, whereas SPL deficiency in gut epithelial cells promotes colitis and colitis-associated carcinogenesis (CAC. Recently, we identified a complex syndrome comprised of nephrosis, adrenal insufficiency, and immunological defects caused by inherited mutations in human SGPL1, the gene encoding SPL. In the present article, we review current evidence supporting the role of SPL in thymic egress, inflammation, and cancer. Lastly, we summarize recent progress in understanding other SPL functions, its role in inherited disease, and SPL targeting for therapeutic purposes.

  7. Some Possible Cases of Escape Mimicry in Neotropical Butterflies.

    Science.gov (United States)

    Pinheiro, C E G; Freitas, A V L

    2014-10-01

    The possibility that escape or evasive mimicry evolved in butterflies and other prey insects in a similar fashion to classical Batesian and Müllerian mimicry has long been advanced in the literature. However, there is a general disagreement among lepidopterists and evolutionary biologists on whether or not escape mimicry exists, as well as in which mimicry rings this form of mimicry has evolved. Here, we review some purported cases of escape mimicry in Neotropical butterflies and suggest new mimicry rings involving several species of Archaeoprepona, Prepona, and Doxocopa (the "bright blue bands" ring) and species of Colobura and Hypna (the "creamy bands" ring) where the palatability of butterflies, their ability to escape predator attacks, geographic distribution, relative abundance, and co-occurrence in the same habitats strongly suggest that escape mimicry is involved. In addition, we also indicate other butterfly taxa whose similarities of coloration patterns could be due to escape mimicry and would constitute important case studies for future investigation.

  8. The atmospheric escape at Mars: complementing the scenario

    Science.gov (United States)

    Lilensten, Jean; Simon, Cyril; Barthélémy, Mathieu; Thissen, Roland; Ehrenreich, David; Gronoff, Guillaume; Witasse, Olivier

    2013-04-01

    In the recent years, the presence of dications in the atmospheres of Mars, Venus, Earth and Titan has been modeled and assessed. These studies also suggested that these ions could participate to the escape of the planetary atmospheres because a large fraction of them is unstable and highly ener- getic. When they dissociate, their internal energy is transformed into kinetic energy which may be larger than the escape energy. This study assesses the impact of the doubly-charged ions in the escape of CO2-dominated planetary atmospheres and to compare it to the escape of thermal photo-ions.We solve a Boltzmann transport equation at daytime taking into account the dissociative states of CO++ for a simplified single constituent atmosphere of a 2 case-study planet. We compute the escape of fast ions using a Beer-Lambert approach. We study three test-cases. On a Mars-analog planet in today's conditions, we retrieve the measured electron escape flux. When comparing the two mechanisms (i.e. excluding solar wind effects, sputtering ...), the escape due to the fast ions issuing from the dissociation of dications may account for up to 6% of the total and the escape of thermal ions for the remaining. We show that these two mechanisms cannot explain the escape of the atmosphere since the magnetic field vanished but complement the other processes and allow writing the scenario of the Mars escape. We show that the atmosphere of a Mars analog planet would empty in another giga years and a half. At Venus orbit, the contribution of the dications in the escape rate is negligible.When simulating the hot Jupiter HD209458b, the two processes cannot explain the measured escape flux of C+.

  9. Histogram analysis of apparent diffusion coefficient maps for assessing thymic epithelial tumours: correlation with world health organization classification and clinical staging.

    Science.gov (United States)

    Kong, Ling-Yan; Zhang, Wei; Zhou, Yue; Xu, Hai; Shi, Hai-Bin; Feng, Qing; Xu, Xiao-Quan; Yu, Tong-Fu

    2018-04-01

    To investigate the value of apparent diffusion coefficients (ADCs) histogram analysis for assessing World Health Organization (WHO) pathological classification and Masaoka clinical stages of thymic epithelial tumours. 37 patients with histologically confirmed thymic epithelial tumours were enrolled. ADC measurements were performed using hot-spot ROI (ADC HS-ROI ) and histogram-based approach. ADC histogram parameters included mean ADC (ADC mean ), median ADC (ADC median ), 10 and 90 percentile of ADC (ADC 10 and ADC 90 ), kurtosis and skewness. One-way ANOVA, independent-sample t-test, and receiver operating characteristic were used for statistical analyses. There were significant differences in ADC mean , ADC median , ADC 10 , ADC 90 and ADC HS-ROI among low-risk thymoma (type A, AB, B1; n = 14), high-risk thymoma (type B2, B3; n = 9) and thymic carcinoma (type C, n = 14) groups (all p-values histogram analysis may assist in assessing the WHO pathological classification and Masaoka clinical stages of thymic epithelial tumours. Advances in knowledge: 1. ADC histogram analysis could help to assess WHO pathological classification of thymic epithelial tumours. 2. ADC histogram analysis could help to evaluate Masaoka clinical stages of thymic epithelial tumours. 3. ADC 10 might be a promising imaging biomarker for assessing and characterizing thymic epithelial tumours.

  10. Effects of marrow grafting on preleukemia cells and thymic nurse cells in C57BL/Ka mice after a leukemogenic split-dose irradiation

    International Nuclear Information System (INIS)

    Defresne, M.P.; Greimers, R.; Lenaerts, P.; Boniver, J.

    1986-01-01

    A split-dose regimen of whole-body irradiation (4 X 175 rad at weekly intervals) induced thymic lymphomas in C57BL/Ka mice after a latent period of 3-9 months. Meanwhile, preleukemia cells arose in the thymus and bone marrow and persisted until the onset of lymphomas. Simultaneously, thymic lymphopoiesis was impaired; thymocyte numbers were subnormal and thymic nurse cells disappeared in a progressive but irreversible fashion. The depletion of these lymphoepithelial complexes, which are normally involved in the early steps of thymic lymphopoiesis, was related to altered prothymocyte activity in bone marrow and to damaged thymic microenvironment, perhaps as a consequence of the presence of preleukemia cells. The grafting of normal bone marrow cells after irradiation prevented the development of lymphomas. However, marrow reconstitution did not inhibit the induction of preleukemia cells. They disappeared from the thymus during the second part of the latent period. At the same time, thymic lymphopoiesis was restored; thymocytes and nurse cell numbers returned to normal as a consequence of the proliferation of grafted marrow-derived cells within the thymus. The results thus demonstrated an intimate relationship between preleukemia cells and an alteration of thymic lymphopoiesis, which particularly involved the nurse cell microenvironment. Some preleukemia cells in marrow-reconstituted, irradiated mice derived from the unirradiated marrow inoculate. Thus these cells acquired neoplastic potential through a factor present in the irradiated tissues. The nature of this indirect mechanism was briefly discussed

  11. Non-thermal escape of molecular hydrogen from Mars

    Science.gov (United States)

    Gacesa, M.; Zhang, P.; Kharchenko, V.

    2012-05-01

    We present a detailed theoretical analysis of non-thermal escape of molecular hydrogen from Mars induced by collisions with hot atomic oxygen from the Martian corona. To accurately describe the energy transfer in O + H2(v, j) collisions, we performed extensive quantum-mechanical calculations of state-to-state elastic, inelastic, and reactive cross sections. The escape flux of H2 molecules was evaluated using a simplified 1D column model of the Martian atmosphere with realistic densities of atmospheric gases and hot oxygen production rates for low solar activity conditions. An average intensity of the non-thermal escape flux of H2 of 1.9 × 105 cm-2s-1 was obtained considering energetic O atoms produced in dissociative recombinations of O2+ ions. Predicted ro-vibrational distribution of the escaping H2 was found to contain a significant fraction of higher rotational states. While the non-thermal escape rate was found to be lower than Jeans rate for H2 molecules, the non-thermal escape rates of HD and D2 are significantly higher than their respective Jeans rates. The accurate evaluation of the collisional escape flux of H2 and its isotopes is important for understanding non-thermal escape of molecules from Mars, as well as for the formation of hot H2 Martian corona. The described molecular ejection mechanism is general and expected to contribute to atmospheric escape of H2 and other light molecules from planets, satellites, and exoplanetary bodies.

  12. Age-Associated Decline in Thymic B Cell Expression of Aire and Aire-Dependent Self-Antigens

    Directory of Open Access Journals (Sweden)

    Sergio Cepeda

    2018-01-01

    Full Text Available Although autoimmune disorders are a significant source of morbidity and mortality in older individuals, the mechanisms governing age-associated increases in susceptibility remain incompletely understood. Central T cell tolerance is mediated through presentation of self-antigens by cells constituting the thymic microenvironment, including epithelial cells, dendritic cells, and B cells. Medullary thymic epithelial cells (mTECs and B cells express distinct cohorts of self-antigens, including tissue-restricted self-antigens (TRAs, such that developing T cells are tolerized to antigens from peripheral tissues. We find that expression of the TRA transcriptional regulator Aire, as well as Aire-dependent genes, declines with age in thymic B cells in mice and humans and that cell-intrinsic and cell-extrinsic mechanisms contribute to the diminished capacity of peripheral B cells to express Aire within the thymus. Our findings indicate that aging may diminish the ability of thymic B cells to tolerize T cells, revealing a potential mechanistic link between aging and autoimmunity.

  13. Tissue-resident natural killer (NK) cells are cell lineages distinct from thymic and conventional splenic NK cells

    Science.gov (United States)

    Sojka, Dorothy K; Plougastel-Douglas, Beatrice; Yang, Liping; Pak-Wittel, Melissa A; Artyomov, Maxim N; Ivanova, Yulia; Zhong, Chao; Chase, Julie M; Rothman, Paul B; Yu, Jenny; Riley, Joan K; Zhu, Jinfang; Tian, Zhigang; Yokoyama, Wayne M

    2014-01-01

    Natural killer (NK) cells belong to the innate immune system; they can control virus infections and developing tumors by cytotoxicity and producing inflammatory cytokines. Most studies of mouse NK cells, however, have focused on conventional NK (cNK) cells in the spleen. Recently, we described two populations of liver NK cells, tissue-resident NK (trNK) cells and those resembling splenic cNK cells. However, their lineage relationship was unclear; trNK cells could be developing cNK cells, related to thymic NK cells, or a lineage distinct from both cNK and thymic NK cells. Herein we used detailed transcriptomic, flow cytometric, and functional analysis and transcription factor-deficient mice to determine that liver trNK cells form a distinct lineage from cNK and thymic NK cells. Taken together with analysis of trNK cells in other tissues, there are at least four distinct lineages of NK cells: cNK, thymic, liver (and skin) trNK, and uterine trNK cells. DOI: http://dx.doi.org/10.7554/eLife.01659.001 PMID:24714492

  14. Osseous oligometastases from thymic carcinoma: a case report suggesting the effectiveness of palliative-intent radiotherapy treatment

    Directory of Open Access Journals (Sweden)

    Kashima J

    2016-02-01

    Full Text Available Jumpei Kashima,1 Hirotoshi Horio,1 Yusuke Okuma,1,2 Yukio Hosomi,1 Tsunekazu Hishima3 1Department of Thoracic Oncology and Respiratory Medicine, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Tokyo, Japan; 2Division of Oncology, Research Center for Medical Sciences, Jikei University School of Medicine, Tokyo, Japan; 3Department of Pathology, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Tokyo, Japan Background: Oligometastasis, a recently proposed concept, is defined as an intermediate state of cancer, between localized and systemic disease, that may be well controlled by local ablative treatment. Thymic carcinoma is a rare cancer with a poor prognosis. A definitive management approach has yet to be confirmed by a high level of evidence.Case presentation: We present the case of a 41-year-old female who underwent curative-intent surgery for a stage III squamous cell carcinoma of the thymus. Bone metastases were detected 1 year later by magnetic resonance imaging. These were treated with palliative-intent radiotherapy. Disease progression has not been observed in more than 15 years since the achievement of complete radiological remission.Conclusion: The treatment outcomes in this and other reported cases suggest that some patients with oligometastatic thymic carcinoma may achieve prolonged survival or even cure with low-dose radiotherapy delivered to the metastases. Keywords: oligometastasis, thymic carcinoma, thymic epithelial tumor, bone metastasis

  15. In vitro evidence for participation of DEC-205 expressed by thymic cortical epithelial cells in clearance of apoptotic thymocytes.

    NARCIS (Netherlands)

    Small, M; Kraal, G.

    2003-01-01

    Binding of apoptotic cells was compared after incubation of thymocytes with two clones of murine thymic stromal cells to which CD4(+)/CD8(+) thymocytes attach. With the BA/10, but not the BA/2, clone, thymocytes with apoptotic morphology were bound irreversibly. These tightly bound thymocytes were

  16. A False Positive I-131 Metastatic Survey Caused by Radioactive Iodine Uptake by a Benign Thymic Cyst

    Directory of Open Access Journals (Sweden)

    Avneet K. Singh

    2017-01-01

    Full Text Available Thyroid carcinoma is the most common endocrine malignancy in the United States with increasing incidence and diagnosis but stable mortality. Differentiated thyroid cancer rarely presents with distant metastases and is associated with a low risk of morbidity and mortality. Despite this, current protocols recommend remnant ablation with radioactive iodine and evaluation for local and distant metastasis in some patients with higher risk disease. There are several case reports of false positive results of metastatic surveys that are either normal physiologic variants or other pathological findings. Most false positive findings are associated with tissue that has physiologic increased uptake of I-131, such as breast tissue or lung tissue; pathological findings such as thymic cysts are also known to have increased uptake. Our case describes a rare finding of a thymic cyst found on a false positive I-131 metastatic survey. The patient was taken for surgical excision and the final pathology was a benign thymic cyst. Given that pulmonary metastases of differentiated thyroid cancer are rare, thymic cysts, though also rare, must be part of the differential diagnosis for false positive findings on an I-131 survey.

  17. Different mechanisms for the resistance of C3H and STS strain mice to the development of thymic lymphomas following fractionated whole-body irradiation

    International Nuclear Information System (INIS)

    Aizawa, Shiro; Kamisaku, Hitoko

    1999-01-01

    B10 strain mice are extremely susceptible for induction of thymic lymphomas by fractionated whole-body irradiation (FI), whereas C3H and STS mice are fairly resistant. In the present study, we constructed radiation bone marrow chimeras in the reciprocal donor-host combinations of susceptible and resistant mice with use of Thy1 markers that allow to determine genetic origins of donor- and host-type thymocytes, and then to analyze the influence of host/thymic environment on the strain-dependent susceptibility to thymic lymphomagenesis. B10.Thy1.1→C3H, B10.Thy1.1→STS as well as B10.Thy1.1→B10 bone marrow chimeras manifested a high incidence of thymic lymphomas after FI-treatment, whereas C3H. Thy1.1→B10 and STS→B10 as well as C3H→C3H and STS→STS chimeras manifested a low incidence of thymic lymphoma. Furthermore, FI-treatment of [B10.Thy1.1+C3H]→B10 mixed chimeras resulted in the generation of similar numbers of thymic lymphomas of B10 and C3H origins, whereas FI-treatment of [B10.Thy1.1+STS]→B10 mixed chimeras preferentially induced thymic lymphomas of B10 origin. These results indicated that host environments of C3H and STS resistant mice are not inhibitory for the development of thymic lymphomas, genetic factors responsible for the strain-dependent susceptibility and/or resistance to FI-induced lymphomagenesis exert their effects entirely on bone-marrow derived cells, and the resistance of STS mice to FI-induced thymic lymphomagenesis is an intrinsic property of thymocytes as the targets of thymic lymphoma induction, whereas bone marrow-derived thymic stroma cells seem to play a significant role in the resistance of C3H mice for the induction of thymic lymphomas. (author)

  18. Thymic lymphocytes. III. Cooperative phenomenon in the proliferation of thymocytes under Con A stimulation.

    Science.gov (United States)

    Papiernik, M; Jacobson, J B

    1986-01-01

    In the present paper, the response of thymocytes to Con A is analyzed in terms of a cooperative phenomenon between medullary thymocytes, cortical thymocytes, thymic accessory cells, and interleukin 2. Medullary thymocytes respond spontaneously to Con A and produce IL-2. The addition of exogenously produced IL-2 enhances their proliferation. Small numbers of cortical (PNA+) thymocytes do not respond to Con A, even in the presence of IL-2-containing supernatant. By increasing the number of PNA+ cells per well, sensitivity to Con A and IL-2 appears. This response may be linked either to the increase in a minor PNA+-responding population and/or to the enhanced contamination by medullary thymocytes and macrophages in non-responding PNA+ thymocyte population. In this hypothesis, either the contaminating cells respond by themselves and/or cooperate with PNA+ cells to induce their proliferation. Coculture of non-responding low numbers of PNA+ thymocytes with Con A- and IL-2-containing supernatant in the presence of PNA- cells containing thymic medullary thymocytes and macrophages always produces a higher response than that of each individual population. These results show that a cooperative phenomenon occurs in the cocultures of PNA+ and PNA- thymic cells. We can show using PNA+ and PNA- thymocytes with different Thy 1 alleles, that indeed both PNA+ and populations participate PNA-thymocytes with different Thy 1 alleles, that indeed both PNA+ and PNA- populations participate in the generation of proliferating cells. We can demonstrate, by lysis experiments with monoclonal antibodies and complement that at the end of coculture, most of the proliferating cells are Lyt 1+, and part are Lyt 2+ or L3T4+. We discuss the fact that the phenotype of the cells after activation does not allow us to deduce the phenotype of their precursors. Lysis of Ia+ cells prior to coculture, reduces the level of the proliferative response but does not modify the percentage of cooperation produced

  19. 30 CFR 75.382 - Mechanical escape facilities.

    Science.gov (United States)

    2010-07-01

    ... with brakes that can stop the fully loaded platform, cage, or other device. (c) Mechanical escape facilities, including automatic elevators, shall be examined weekly. The weekly examination of this equipment... cages, platforms, or elevators. (e) Mechanical escape facilities shall have rated capacities consistent...

  20. Teachers Offering Healthy Escape Options for Teenagers in Pain

    Science.gov (United States)

    Kaywell, Joan F.

    2005-01-01

    "[T]wenty-five percent of today's teenagers have inordinate emotional baggage beyond the normal angst of adolescence." This burden can lead to unhealthy escapes, including substance abuse, sexual activity, violence, eating disorders, and suicide. One healthy escape, however, lies in books, where students can read about teenagers living in painful…

  1. Escape of protists in predator-generated feeding currents

    DEFF Research Database (Denmark)

    Jakobsen, Hans Henrik

    2002-01-01

    The ciliate Strobilidium sp. and 2 flagellates, Chrysochromulina simplex and Gymnodinium sp., were exposed to predator-generated feeding currents, and their escape responses were quantified using 2- and 3-dimensional video techniques. All 3 studied organisms responded by escaping at a defined dis...

  2. Induction of epithelial to mesenchymal transition (EMT) and inhibition on adipogenesis: Two different sides of the same coin? Feasible roles and mechanisms of transforming growth factor β1 (TGF-β1) in age-related thymic involution.

    Science.gov (United States)

    Tan, Jianxin; Wang, Yajun; Zhang, Nannan; Zhu, Xike

    2016-08-01

    Age-related thymic involution is characterized by a loss of thymic epithelial cells (TECs) and a concomitant increase in adipocytes, but the mechanisms involved in thymic adipogenesis are still not clear. Transforming growth factor β1 (TGF-β1) is a pleiotropic cytokine that has been reported to be up-regulated with age in thymic stromal cells in both human and mouse. However, the exact role of TGF-β1 in age-related thymic involution remains to be further elucidated. On the basis of previous findings, we propose a novel hypothesis that TGF-β1 functions a dual role in age-related thymic involution. On one hand, up-regulation of TGF-β1 promotes epithelial to mesenchymal transition (EMT) process in TECs via activating forkhead box protein C2 (FoxC2). On the other hand, TGF-β1 inhibits the transdifferentiation of EMT-derived mesenchymal cells to adipocytes in the thymus. If confirmed, our hypothesis will not only provide further evidence supporting that the transdifferentiation of TECs into pre-adipocytes represents a source of thymic adiposity during age-related thymic involution, but also uncover a unique role of TGF-β1 in the transdifferentiation of TECs into pre-adipocytes. Collectively, the inhibition of TGF-β1 may serve as a strategy to hinder age-related thymic involution or even to restore thymic function in the elderly. © 2016 International Federation for Cell Biology.

  3. Unique loss of heterozygosity of murine thymic lymphomas as a candidate of radiation signature

    Energy Technology Data Exchange (ETDEWEB)

    Shimada, Yoshiya; Nishimura, Mayumi; Kakinuma, Shizuko [National Inst. of Radiological Sciences, Chiba (Japan); Wakana, Shigeharu; Okumoto, Masaaki

    1999-06-01

    Signature(s) of prior exposure to carcinogens have immediate application to the identification of environmental risk factors. Such signatures have been sought to aid in developing policies for the protection from risks of environmental carcinogens. Although ionizing radiation is a potent carcinogenic agent, little is known about possible radiation signatures. This is because radiation induces a broad spectrum of DNA lesions. Here we describe a diversity of K-ras mutations and a unique locus with frequent loss of heterozygisity (LOH) on chromosome 11 of radiation induced thymic lymphomas. The latter locus has never been observed to be similarly altered in either ethylnitrosourea-induced or spontaneously developed lymphomas. These results describe, to our knowledge for the first time, a molecular basis for radiation signature. (author)

  4. The diagnosis of thymoma and thymic atrophy in patients with myasthenia gravis; Dignostikk av tymom og thymusatrofi hos pasienter med myasthenia gravis

    Energy Technology Data Exchange (ETDEWEB)

    Sund, K.K.; Skeie, G.O.; Gilhus, N.E.; Aarli, J.A.; Varhaug, J.E. [Haukeland Sykehus, Bergen (Norway)

    1997-11-01

    The authors have compared clinical, immunological and radiological data in 20 patients with myasthenia gravis and thymoma and in 21 patients with myasthenia gravis and thymic atrophy. The median age at onset was 54 years in the thymoma group and 63 years in the thymic atrophy group. The severity of the disease was similar in the two groups, and there was no significant difference in the concentration of acetylcholine receptor antibodies. CA antibodies were demonstrated in 17/20 thymoma patients and in 6/21 with thymic atrophy, while 19/20 thymoma patients had antibodies to titin, compared with 9/21 among those with thymic atrophy. The diagnosis and treatment of patients with myasthenia gravis is based upon an evaluation of clinical, immunological and radiological data. 28 refs., 2 tabs.

  5. Influence of age on the proliferation and peripheralization of thymic T cells

    International Nuclear Information System (INIS)

    Hirokawa, K.; Utsuyama, M.; Katsura, Y.; Sado, T.

    1988-01-01

    Bone marrow cells obtained from B10.Thy-1.1 mice (H-2b, Thy-1.1) were injected directly into the thymus of C57BL/6 mice (H-2b,Thy 1.2) of various ages. Thymocyte precursors in the injected donor-bone marrow cells could proliferate in the thymic microenvironment in the following manner: first, preferentially proliferating into the subcapsular cortex; and second, spreading to the whole layer of the cortex, a portion of them gradually moving into the medulla. The proliferation of donor-type thymocytes was most pronounced when intrathymic injection of bone marrow cells (ITB) was performed in newborn mice and especially prominent in week-old mice; it took approximately ten weeks for donor-type thymocytes to finish the whole course of proliferation, differentiation, and emigration to the periphery. When ITB was performed in mice 4 weeks of age and older, the proliferation of donor-type thymocytes was retarded at onset, less pronounced in magnitude, and disappeared earlier. Emigration of donor-type T cells from the thymus to the peripheral lymphoid tissues occurred most rapidly when ITB was performed in newborn mice, and these T cells continued to reside thereafter in the peripheral lymphoid tissues. However, when ITB was performed in mice 4 weeks of age and older, the number of emigrated T cells in the spleen decreased (about a tenth of that in newborn mice) and, moreover, these T cells resided only transiently in the spleen. It was suggested that T cells emigrating from the thymus of mice from newborn to 2 weeks of age are long-lived, whereas those from the thymus in mice 4 weeks of age and older are short-lived. However, when 4-week-old young adult mice were treated by irradiation or hydrocortisone, the thymic capacity was enhanced in terms of proliferation and peripheralization of thymocytes, and emigrated T cells became long-lived

  6. Origins and Properties of Dental, Thymic, and Bone Marrow Mesenchymal Cells and Their Stem Cells

    Science.gov (United States)

    Komada, Yukiya; Yamane, Toshiyuki; Kadota, Daiji; Isono, Kana; Takakura, Nobuyuki; Hayashi, Shin-Ichi; Yamazaki, Hidetoshi

    2012-01-01

    Mesenchymal cells arise from the neural crest (NC) or mesoderm. However, it is difficult to distinguish NC-derived cells from mesoderm-derived cells. Using double-transgenic mouse systems encoding P0-Cre, Wnt1-Cre, Mesp1-Cre, and Rosa26EYFP, which enabled us to trace NC-derived or mesoderm-derived cells as YFP-expressing cells, we demonstrated for the first time that both NC-derived (P0- or Wnt1-labeled) and mesoderm-derived (Mesp1-labeled) cells contribute to the development of dental, thymic, and bone marrow (BM) mesenchyme from the fetal stage to the adult stage. Irrespective of the tissues involved, NC-derived and mesoderm-derived cells contributed mainly to perivascular cells and endothelial cells, respectively. Dental and thymic mesenchyme were composed of either NC-derived or mesoderm-derived cells, whereas half of the BM mesenchyme was composed of cells that were not derived from the NC or mesoderm. However, a colony-forming unit-fibroblast (CFU-F) assay indicated that CFU-Fs in the dental pulp, thymus, and BM were composed of NC-derived and mesoderm-derived cells. Secondary CFU-F assays were used to estimate the self-renewal potential, which showed that CFU-Fs in the teeth, thymus, and BM were entirely NC-derived cells, entirely mesoderm-derived cells, and mostly NC-derived cells, respectively. Colony formation was inhibited drastically by the addition of anti-platelet–derived growth factor receptor-β antibody, regardless of the tissue and its origin. Furthermore, dental mesenchyme expressed genes encoding critical hematopoietic factors, such as interleukin-7, stem cell factor, and cysteine-X-cysteine (CXC) chemokine ligand 12, which supports the differentiation of B lymphocytes and osteoclasts. Therefore, the mesenchymal stem cells found in these tissues had different origins, but similar properties in each organ. PMID:23185234

  7. Mediastinal neoplasms in patients with Graves disease: a possible link between sustained hyperthyroidism and thymic neoplasia?

    Directory of Open Access Journals (Sweden)

    Boyd Jonathan D

    2012-07-01

    Full Text Available Abstract Background Anterior mediastinal masses are a rare but well documented finding in Graves disease. The vast majority of these lesions represents benign thymic hypertrophy and regress after treatment of the hyperthyroidism. A small percentage of these cases however represent neoplastic/malignant diseases which require further treatment. Cases 12 year old boy with one year history of refractory Graves disease was found to have an anterior mediastinal mass and underwent curative thyroidectomy for sustained hyperthyroidism. Cervical lymphadenopathy was detected during the procedure and biopsy was obtained. A 23 year old woman who presented with a one month history of hyperthyroid symptoms, was diagnosed with Graves disease and also was found to have an anterior mediastinal mass on imaging. Biopsy of the anterior mediastinal mass was obtained and subsequently the patient underwent robotic thymectomy. Histologic examination and immunophenotyping of the cervical lymph node in a 12 year old boy revealed neoplastic proliferation of T lymphoblasts diagnostic of T lymphoblastic leukemia/lymphoma. Examination of the anterior mediastinal mass biopsy in the 23 year old woman revealed type B1 thymoma which was confirmed after examination of the subsequent robotic thymectomy specimen. Conclusion This is the first reported case of T cell lymphoblastic lymphoma and the third reported case of thymoma associated with sustained hyperthyroidism due to Graves disease. These cases indicate that an anterior mediastinal mass in a patient with active Graves disease may be due to a neoplastic cause, which may require definitive treatment. Caution should be exercised when dismissing a mediastinal mass as benign thymic hyperplasia in patients with active Graves disease.

  8. Selective lymphoid irradiation. V. Synergism with pretransplant thymectomy or thymic irradiation in cardiac transplantation in rats

    International Nuclear Information System (INIS)

    Iga, C.; Fawwaz, R.; Nowygrod, R.; Reemtsma, K.; Hardy, M.A.

    1985-01-01

    Selective lymphoid irradiation (SLI) using palladium-109-hematoporphyrin (Pd-H), given four days prior to transplantation, combined with two doses of antilymphocyte globulin (ALG) (10 mg, days -2 and -1), was evaluated as a method of induction of permanent heterotopic cardiac allograft survival in the highly histoincompatible rat strain combination of ACI (RT1(1))-to-Lewis (RT1a). Both Pd-H and ALG localize poorly in the thymus, so this study evaluated whether thymic irradiation (TI) or thymectomy (TX) of the adult recipient results in indefinite allograft survival. Immunosuppression with Pd-H or ALG alone gave a mean survival time (MST) of 6.7 +/- 0.6 days, but the combination of the two agents led to an MST of 17.6 +/- 3.4 days. When TI was combined with Pd-H and ALG, cardiac allograft survival was prolonged to 50.2 +/- 13.9 days, but TI alone showed an MST of 10.3 +/- 1.8 days. Permanent cardiac allograft survival (greater than 250 days) was achieved in all thymectomized recipients treated with the combination of Pd-H and a brief course of ALG. These animals also accepted second-set skin grafts and rejected third-party skin grafts following more than 150 days of ACI cardiac allograft survival. Thymic irradiation, although effective in acting synergistically with SLI and ALG, led to prolonged, but limited allograft survival, although thymectomy with SLI and ALG is synergistic in prolonging allograft survival permanently without chronic immunosuppression

  9. Analysis of early initiating event(s) in radiation-induced thymic lymphomagenesis

    International Nuclear Information System (INIS)

    Muto, Masahiro; Ying Chen; Kubo, Eiko; Mita, Kazuei

    1996-01-01

    Since the T cell receptor rearrangement is a sequential process and unique to the progeny of each clone, we investigated the early initiating events in radiation-induced thymic lymphomagenesis by comparing the oncogenic alterations with the pattern of γ T cell receptor (TCR) rearrangements. We reported previously that after leukemogenic irradiation, preneoplastic cells developed, albeit infrequently, from thymic leukemia antigen-2 + (TL-2 + ) thymocytes. Limited numbers of TL-2 + cells from individual irradiated B10.Thy-1.1 mice were injected into B10.Thy-1.2 mice intrathymically, and the common genetic changes among the donor-type T cell lymphomas were investigated with regard to p53 gene and chromosome aberrations. The results indicated that some mutations in the p53 gene had taken place in these lymphomas, but there was no common mutation among the donor-type lymphomas from individual irradiated mice, suggesting that these mutations were late-occurring events in the process of oncogenesis. On the other hand, there were common chromosome aberrations or translocations such as trisomy 15, t(7F; 10C), t(1A; 13D) or t(6A; XB) among the donor-type lymphomas derived from half of the individual irradiated mice. This indicated that the aberrations/translocations, which occurred in single progenitor cells at the early T cell differentiation either just before or after γ T cell receptor rearrangements, might be important candidates for initiating events. In the donor-type lymphomas from the other half of the individual irradiated mice, microgenetic changes were suggested to be initial events and also might take place in single progenitor cells just before or right after γ TCR rearrangements. (author)

  10. Immune escape strategies of malaria parasites

    Directory of Open Access Journals (Sweden)

    Pollyanna Stephanie Gomes

    2016-10-01

    Full Text Available Malaria is one of the most life-threatening infectious diseases worldwide. Immunity to malaria is slow and short-lived despite the repeated parasite exposure in endemic areas. Malaria parasites have evolved refined machinery to evade the immune system based on a range of genetic changes that include allelic variation, biomolecular exposure of proteins and intracellular replication. All of these features increase the probability of survival in both mosquitoes and the vertebrate host. Plasmodium species escape from the first immunological trap in its invertebrate vector host, the Anopheles mosquitoes. The parasites have to pass through various immunological barriers within the mosquito such as anti-microbial molecules and the mosquito microbiota in order to achieve successful transmission to the vertebrate host. Within these hosts, Plasmodium species employ various immune evasion strategies during different life cycle stages. Parasite persistence against the vertebrate immune response depends on the balance among virulence factors, pathology, metabolic cost of the host immune response, and the parasites ability to evade the immune response. In this review we discuss the strategies that Plasmodium parasites use to avoid the vertebrate host immune system and how they promote successful infection and transmission.

  11. Nonthermal atmospheric escape from Mars and Titan

    International Nuclear Information System (INIS)

    Lammer, H.; Bauer, S.J.

    1991-01-01

    Energy flux spectra and particle concentrations of the hot O and N coronae from Mars and Titan, respectively, resulting primarily from dissociative recombination of molecular ions, have been calculated by means of a Monte Carlo method. The calculated energy flux spectra lead to an escape flux null esc ∼ 6 x 10 6 cm -2 s -1 for Mars and null esc ∼ 2 x 10 6 cm -2 s -1 for Titan, corresponding to a mass loss of about 0.14 kg/s for Mars and about 0.3 kg/s for Titan. (The contribution of electron impact ionization on N 2 amounts to only about 25% of Titan's mass loss.) Mass loss via solar and magnetospheric wind is also estimated using newly calculated mass loading limits. The mass loss via ion pickup from the extended hot atom corona for Mars amounts to about 0.25 kg/s (O + ) and for Titan to about 50 g/s (N 2 + or H 2 CN + ). Thus, the total mass loss rate from Mars and Titan is about the same, i.e., 0.4 kg/s

  12. Leishmania Hijacks Myeloid Cells for Immune Escape

    Directory of Open Access Journals (Sweden)

    María Martínez-López

    2018-05-01

    Full Text Available Protozoan parasites of the Leishmania genus are the causative agents of leishmaniasis, a group of neglected tropical diseases whose clinical manifestations vary depending on the infectious Leishmania species but also on host factors. Recognition of the parasite by host myeloid immune cells is a key to trigger an effective Leishmania-specific immunity. However, the parasite is able to persist in host myeloid cells by evading, delaying and manipulating host immunity in order to escape host resistance and ensure its transmission. Neutrophils are first in infiltrating infection sites and could act either favoring or protecting against infection, depending on factors such as the genetic background of the host or the parasite species. Macrophages are the main host cells where the parasites grow and divide. However, macrophages are also the main effector population involved in parasite clearance. Parasite elimination by macrophages requires the priming and development of an effector Th1 adaptive immunity driven by specific subtypes of dendritic cells. Herein, we will provide a comprehensive outline of how myeloid cells regulate innate and adaptive immunity against Leishmania, and the mechanisms used by the parasites to promote their evasion and sabotage. Understanding the interactions between Leishmania and the host myeloid cells may lead to the development of new therapeutic approaches and improved vaccination to leishmaniases, an important worldwide health problem in which current therapeutic or preventive approaches are limited.

  13. Escape route simulator utilizing augmented reality

    Energy Technology Data Exchange (ETDEWEB)

    Mattos, Karen Salazar Ribeiro de; Mó, Antônio Carlos de A.; Santo, André Cotelli do E.; Silva, Marcio Henrique, E-mail: karensalazar.1190@gmail.com [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Centro Universitário Carioca (UniCarioca), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    Due to increasing demand and interest in the interaction of technology platforms and integration of different types of systems and technologies, some tools are already providing practical ways to develop integrated applications. The tools explored by this article are Unity, a platform for game development, and Vuforia, an SDK, software development kit, for augmented reality creation. The coalition proposal of these resources is to create an intuitive escape route that can be used for the evacuation of buildings or open spaces in view of imminent danger, such as radiation leakage, and that can be accessed from a target available at the institution. It has also the intention of simulating situations that involve training of personnel in order to obtain methods that allow to save financial resources, and even to avoid that those who are involved are exposed to risks unnecessarily. The simulator is expected to help design, test, and improve ways to maintain the physical integrity of the facility and provide end users with a better sense of immersion and attractiveness. (author)

  14. Escape route simulator utilizing augmented reality

    International Nuclear Information System (INIS)

    Mattos, Karen Salazar Ribeiro de; Mó, Antônio Carlos de A.; Santo, André Cotelli do E.; Silva, Marcio Henrique

    2017-01-01

    Due to increasing demand and interest in the interaction of technology platforms and integration of different types of systems and technologies, some tools are already providing practical ways to develop integrated applications. The tools explored by this article are Unity, a platform for game development, and Vuforia, an SDK, software development kit, for augmented reality creation. The coalition proposal of these resources is to create an intuitive escape route that can be used for the evacuation of buildings or open spaces in view of imminent danger, such as radiation leakage, and that can be accessed from a target available at the institution. It has also the intention of simulating situations that involve training of personnel in order to obtain methods that allow to save financial resources, and even to avoid that those who are involved are exposed to risks unnecessarily. The simulator is expected to help design, test, and improve ways to maintain the physical integrity of the facility and provide end users with a better sense of immersion and attractiveness. (author)

  15. When negation is not negation

    OpenAIRE

    Milicevic, Nataša

    2008-01-01

    In this paper I will discuss the formation of different types of yes/no questions in Serbian (examples in (1)), focusing on the syntactically and semantically puzzling example (1d), which involves the negative auxiliary inversion. Although there is a negative marker on the fronted auxiliary, the construction does not involve sentential negation. This coincides with the fact that the negative quantifying NPIs cannot be licensed. The question formation and sentential negation have similar synta...

  16. An evaluation of two differential reinforcement procedures with escape extinction to treat food refusal.

    Science.gov (United States)

    Patel, Meeta R; Piazza, Cathleen C; Martinez, Cheryl J; Volkert, Valerie M; Christine, M Santana

    2002-01-01

    Consumption of solids and liquids occurs as a chain of behaviors that may include accepting, swallowing, and retaining the food or drink. In the current investigation, we evaluated the relative effectiveness of differential reinforcement of the first behavior in the chain (acceptance) versus differential reinforcement for the terminal behavior in the chain (mouth clean). Three children who had been diagnosed with a feeding disorder participated. Acceptance remained at zero when differential reinforcement contingencies were implemented for acceptance or mouth clean. Acceptance and mouth clean increased for all 3 participants once escape extinction was added to the differential reinforcement procedures, independent of whether reinforcement was provided for acceptance or for mouth clean. Maintenance was observed in 2 children when escape extinction was removed from the treatment package. The mechanism by which consumption increased is discussed in relation to positive and negative reinforcement contingencies.

  17. Dications and thermal ions in planetary atmospheric escape

    Science.gov (United States)

    Lilensten, J.; Simon Wedlund, C.; Barthélémy, M.; Thissen, R.; Ehrenreich, D.; Gronoff, G.; Witasse, O.

    2013-01-01

    In the recent years, the presence of dications in the atmospheres of Mars, Venus, Earth and Titan has been modeled and assessed. These studies also suggested that these ions could participate to the escape of the planetary atmospheres because a large fraction of them is unstable and highly energetic. When they dissociate, their internal energy is transformed into kinetic energy which may be larger than the escape energy. The goal of this study is to assess the impact of the doubly-charged ions in the escape of CO2-dominated planetary atmospheres and to compare it to the escape of thermal photo-ions. We solve a Boltzmann transport equation at daytime taking into account the dissociative states of CO2++ for a simplified single constituent atmosphere of a case-study planet. We compute the escape of fast ions using a Beer-Lambert approach. We study three test-cases. On a Mars-analog planet in today's conditions, we retrieve the measured electron escape flux. When comparing the two mechanisms (i.e. excluding solar wind effects, sputtering, etc.), the escape due to the fast ions issuing from the dissociation of dications may account for up to 6% of the total and the escape of thermal ions for the remaining. We show that these two mechanisms cannot explain the escape of the atmosphere since the magnetic field vanished and even contribute only marginally to this loss. We show that with these two mechanisms, the atmosphere of a Mars analog planet would empty in another giga years and a half. At Venus orbit, the contribution of the dications in the escape rate is negligible. When simulating the hot Jupiter HD 209458 b, the two processes cannot explain the measured escape flux of C+. This study shows that the dications may constitute a source of the escape of planetary atmospheres which had not been taken into account until now. This source, although marginal, is not negligible. The influence of the photoionization is of course large, but cannot explain alone the loss of Mars

  18. Unusual Thymic Hyperplasia Mimicking Lipomatous Tumor in an Eight-Year-Old Boy with Concomitant Pericardial Lipomatosis and Right Facial Hemihypertrophy

    International Nuclear Information System (INIS)

    Kim, Yoo Jin; Kim Woo Sun; Cheon, Jung Eun; Lim, Yun Jung; Kim, In One; Yeon, Kyung Mo; Jung, Kyeong Cheon; Byun, Sun Ju

    2011-01-01

    We report a case of thymic hyperplasia accompanied by pericardial lipomatosis and right facial hemihypertrophy in an 8-year-old boy. On imaging studies, the hyperplastic thymus had prominent curvilinear and nodular fatty areas simulating a fat-containing anterior mediastinal mass, which is an unusual finding in children. To our knowledge, this is the first report on a child with a combination of thymic hyperplasia, pericardial lipomatosis, and right facial hemihypertrophy. The radiologic findings are presented with a brief discussion.

  19. Impact of ocean acidification on the early development and escape behavior of marine medaka (Oryzias melastigma).

    Science.gov (United States)

    Wang, Xiaojie; Song, Lulu; Chen, Yi; Ran, Haoyu; Song, Jiakun

    2017-10-01

    Ocean acidification is predicted to affect a wide diversity of marine organisms. However, no studies have reported the effects of ocean acidification on Indian Ocean fish. We have used the Indian Ocean medaka (Oryzias melastigma) as a model species for a marine fish that lives in coastal waters. We investigated the impact of ocean acidification on the embryonic development and the stereotyped escape behavior (mediated by the Mauthner cell) in newly hatched larvae. Newly fertilized eggs of medaka were reared in seawater at three different partial pressures of carbon dioxide (pCO 2 ): control at 450 μatm, moderate at 1160 μatm, and high at 1783 μatm. Hatch rates, embryonic duration, and larval malformation rates were compared and were not significantly different between the treatments and the control. In the high pCO 2 group, however, the yolks of larvae were significantly smaller than in the control group, and the newly hatched larvae were significantly longer than the larvae in the control. In the moderate pCO 2 group, the eye distance decreased significantly. No significantly negative growth effects were observed in the larvae when exposed to pCO 2 levels that are predicted as a result of ocean acidification in the next 100-200 years. Larvae reared under control conditions readily produced C-start escape behavior to mechanosensory stimuli; however, in the moderate and high pCO 2 experimental groups, the probabilities of C-start were significantly lower than those of the control group. Therefore, the sensory integration needed for the C-start escape behavior appears to be vulnerable to ocean acidification. Altered behavior in marine larval fish, particularly behaviors involved in escape from predation, could have potentially negative implications to fish populations, and, further, to the marine ecosystems at the levels of CO 2 projected for the future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Light escape cones in local reference frames of Kerr-de Sitter black hole spacetimes and related black hole shadows

    Science.gov (United States)

    Stuchlík, Zdeněk; Charbulák, Daniel; Schee, Jan

    2018-03-01

    We construct the light escape cones of isotropic spot sources of radiation residing in special classes of reference frames in the Kerr-de Sitter (KdS) black hole spacetimes, namely in the fundamental class of `non-geodesic' locally non-rotating reference frames (LNRFs), and two classes of `geodesic' frames, the radial geodesic frames (RGFs), both falling and escaping, and the frames related to the circular geodesic orbits (CGFs). We compare the cones constructed in a given position for the LNRFs, RGFs, and CGFs. We have shown that the photons locally counter-rotating relative to LNRFs with positive impact parameter and negative covariant energy are confined to the ergosphere region. Finally, we demonstrate that the light escaping cones govern the shadows of black holes located in front of a radiating screen, as seen by the observers in the considered frames. For shadows related to distant static observers the LNRFs are relevant.

  1. A New Paradigm for Evaluating Avoidance/Escape Motivation.

    Science.gov (United States)

    Tsutsui-Kimura, Iku; Bouchekioua, Youcef; Mimura, Masaru; Tanaka, Kenji F

    2017-07-01

    Organisms have evolved to approach pleasurable opportunities and to avoid or escape from aversive experiences. These 2 distinct motivations are referred to as approach and avoidance/escape motivations and are both considered vital for survival. Despite several recent advances in understanding the neurobiology of motivation, most studies addressed approach but not avoidance/escape motivation. Here we develop a new experimental paradigm to quantify avoidance/escape motivation and examine the pharmacological validity. We set up an avoidance variable ratio 5 task in which mice were required to press a lever for variable times to avoid an upcoming aversive stimulus (foot shock) or to escape the ongoing aversive event if they failed to avoid it. We i.p. injected ketamine (0, 1, or 5 mg/kg) or buspirone (0, 5, or 10 mg/kg) 20 or 30 minutes before the behavioral task to see if ketamine enhanced avoidance/escape behavior and buspirone diminished it as previously reported. We found that the performance on the avoidance variable ratio 5 task was sensitive to the intensity of the aversive stimulus. Treatment with ketamine increased while that with buspirone decreased the probability of avoidance from an aversive stimulus in the variable ratio 5 task, being consistent with previous reports. Our new paradigm will prove useful for quantifying avoidance/escape motivation and will contribute to a more comprehensive understanding of motivation. © The Author 2017. Published by Oxford University Press on behalf of CINP.

  2. MAVEN Pickup Ion Constraints on Mars Neutral Escape

    Science.gov (United States)

    Rahmati, A.; Larson, D. E.; Cravens, T.; Lillis, R. J.; Dunn, P.; Halekas, J. S.; McFadden, J. P.; Mitchell, D. L.; Thiemann, E.; Connerney, J. E. P.; DiBraccio, G. A.; Espley, J. R.; Eparvier, F. G.

    2017-12-01

    Mars is currently losing its atmosphere mainly due to the escape of neutral hydrogen and oxygen. Directly measuring the rate of escaping neutrals is difficult, because the neutral density in the Mars exosphere is dominated, up to several Martian radii, by atoms that are gravitationally bound to the planet. Neutral atoms in the Martian exosphere, however, can get ionized, picked up, and accelerated by the solar wind motional electric field and energized to energies high enough for particle detectors to measure them. The MAVEN SEP instrument detects O+ pickup ions that are created at altitudes where the escaping part of the exosphere is dominant. Fluxes of these ions reflect neutral densities in the distant exosphere of Mars, allowing us to constrain neutral oxygen escape rates. The MAVEN SWIA and STATIC instruments measure pickup H+ and O+ created closer to Mars; comparisons of these data with models can be used to constrain exospheric hot O and thermal H densities and escape rates. In this work, pickup ion measurements from SEP, SWIA, and STATIC, taken during the first 3 Earth years of the MAVEN mission, are compared to the outputs of a pickup ion model to constrain the variability of neutral escape at Mars. The model is based on data from six MAVEN instruments, namely, MAG providing magnetic field used in calculating pickup ion trajectories, SWIA providing solar wind velocity as well as 3D pickup H+ and O+ spectra, SWEA providing solar wind electron spectrum used in electron impact ionization rate calculations, SEP providing pickup O+ spectra, STATIC providing mass resolved 3D pickup H+ and O+ spectra, and EUVM providing solar EUV spectra used in photoionization rate calculations. A variability of less than a factor of two is observed in hot oxygen escape rates, whereas thermal escape of hydrogen varies by an order of magnitude with Mars season. This hydrogen escape variability challenges our understanding of the H cycle at Mars, but is consistent with other

  3. Osseous oligometastases from thymic carcinoma: a case report suggesting the effectiveness of palliative-intent radiotherapy treatment.

    Science.gov (United States)

    Kashima, Jumpei; Horio, Hirotoshi; Okuma, Yusuke; Hosomi, Yukio; Hishima, Tsunekazu

    2016-01-01

    Oligometastasis, a recently proposed concept, is defined as an intermediate state of cancer, between localized and systemic disease, that may be well controlled by local ablative treatment. Thymic carcinoma is a rare cancer with a poor prognosis. A definitive management approach has yet to be confirmed by a high level of evidence. We present the case of a 41-year-old female who underwent curative-intent surgery for a stage III squamous cell carcinoma of the thymus. Bone metastases were detected 1 year later by magnetic resonance imaging. These were treated with palliative-intent radiotherapy. Disease progression has not been observed in more than 15 years since the achievement of complete radiological remission. The treatment outcomes in this and other reported cases suggest that some patients with oligometastatic thymic carcinoma may achieve prolonged survival or even cure with low-dose radiotherapy delivered to the metastases.

  4. Thymic involvement in immune recovery during antiretroviral treatment of HIV infection in adults; comparison of CT and sonographic findings

    DEFF Research Database (Denmark)

    Kolte, Lilian; Strandberg, Charlotte; Dreves, Anne-Mette

    2002-01-01

    ) repertoire were determined. The study demonstrated no correlation between the 2 scanning methods (r = 0.201, p = 0.358 in patients and r = 0.457, p = 0.184 in controls). Among the patients, no association was found between the sonographically estimated thymic size and immunological parameters such as CD4...... count (r = 0.083, p = 0.706), naive CD4 count (r = 0.067, p = 0.762), CD4 + TREC frequency (r = 0.028, p = 0.900) and CD4 + TCR repertoire (r = -0.057, p = 0.828). These findings show that CT remains superior for assessing thymic size in adults and is preferable to ultrasound when evaluating...

  5. Diagnostic value of plain chest roentgenogram and CT scan findings in four cases of massive thymic hyperplasia

    International Nuclear Information System (INIS)

    Kobayashi, T.; Hirabayashi, Y.; Kobayashi, Y.

    1986-01-01

    Massive thymic hyperplasia (MTH) is rare in the pediatric age group, especially in infants. However, because of a wide variation in size and weight of the thymus, an enlarged gland is often resected because of suspicion of a neoplasm or a cyst. Some cases of thymoma resembling pulmonary acute infection occur less frequently than MTH, but if respiratory problems are accompanied by a large thymus immediate diagnosis is often necessary to differentiate between these two conditions. Four infants (14 days to 4 months of age) with MTH were recently studied, all having an acute onset an of severe respiratory distress. The infants were referred to our center with a tentative diagnosis of thymic or other intrathoracic tumors. The following case reports illustrate our diagnostic approach to evaluate patients with symptoms suggesting MTH and the response to the ''steroid test''. (orig.)

  6. Identification of differentially expressed proteins in spontaneous thymic lymphomas from knockout mice with deletion of p53

    DEFF Research Database (Denmark)

    Honoré, Bent; Buus, Søren; Claësson, Mogens H

    2008-01-01

    ABSTRACT: BACKGROUND: Knockout mice with a deletion of p53 spontaneously develop thymic lymphomas. Two cell lines (SM5 and SM7), established from two independent tumours, exhibited about fifty to seventy two-fold differentially expressed proteins compared to wild type thymocytes by two-dimensiona......ABSTRACT: BACKGROUND: Knockout mice with a deletion of p53 spontaneously develop thymic lymphomas. Two cell lines (SM5 and SM7), established from two independent tumours, exhibited about fifty to seventy two-fold differentially expressed proteins compared to wild type thymocytes by two...... alpha type 3, transforming acidic coiled-coil containing protein 3, mitochondrial ornithine aminotransferase and epidermal fatty acid binding protein and down-regulation of adenylosuccinate synthetase, tubulin beta-3 chain, a 25 kDa actin fragment, proteasome subunit beta type 9, cofilin-1 and glia...

  7. B and T lymphocytes in man. I. Effect of infant thymic irradiation on the circulating B and T lymphocytes

    International Nuclear Information System (INIS)

    Reddy, M.M.; Goh, K.; Hempelmann, L.H.

    1976-01-01

    B and T lymphocytes were studied in a group of adults whose thymic glands were irradiated in infancy for alleged thymic enlargement. Two independent methods were used to determine the B and T lymphocytes from each peripheral blood specimen: (1) the relative proportion of cells with surface immunoglobulins (B lymphocytes) and cells forming rosettes with sheep erythrocytes (T lymphocytes); and (2) the relative mitogenic response to phytohemagglutinin (T lymphocytes) and to pokeweed mitogen (B lymphocytes). All specimens were coded. The results obtained indicate: (1) a reduction of B and T lymphocytes; and (2) a decreased mitogenic response of lymphocytes to phytohemagglutinin and pokeweed mitogen in this group of patients as compared with the controls. These observations suggest that (1) the effect of irradiation to the thymus gland on lymphocytes is long lasting and (2) both B and T lymphocytes are affected by irradiation to the thymus gland

  8. Long-term persistence of functional thymic epithelial progenitor cells in vivo under conditions of low FOXN1 expression

    DEFF Research Database (Denmark)

    Jin, Xin; Nowell, Craig S; Ulyanchenko, Svetlana

    2014-01-01

    does not require FOXN1. Here, we have used a revertible severely hypomorphic allele of Foxn1, Foxn1R, to test the stability of the common TEPC in vivo. By reactivating Foxn1 expression postnatally in Foxn1R/- mice we demonstrate that functional TEPCs can persist in the thymic rudiment until at least 6...... months of age, and retain the potential to give rise to both cortical and medullary thymic epithelial cells (cTECs and mTECs). These data demonstrate that the TEPC-state is remarkably stable in vivo under conditions of low Foxn1 expression, suggesting that manipulation of FOXN1 activity may prove...... a valuable method for long term maintenance of TEPC in vitro....

  9. Negative mass

    International Nuclear Information System (INIS)

    Hammond, Richard T

    2015-01-01

    Some physical aspects of negative mass are examined. Several unusual properties, such as the ability of negative mass to penetrate any armor, are analysed. Other surprising effects include the bizarre system of negative mass chasing positive mass, naked singularities and the violation of cosmic censorship, wormholes, and quantum mechanical results as well. In addition, a brief look into the implications for strings is given. (paper)

  10. Escape/Aggression Incidence in Sexually Abused Juvenile Delinquents.

    Science.gov (United States)

    Reich, John W.; Gutierres, Sara E.

    1979-01-01

    Reports a continuation of prior research testing a theoretical model which predicts that juveniles subjected to abuse will not become aggressive but will engage in escape and social avoidance behaviors. Analysis supported the hypothesis. (Author)

  11. 30 CFR 57.11053 - Escape and evacuation plans.

    Science.gov (United States)

    2010-07-01

    ... of principal air flow, location of escape routes and locations of existing telephones, primary fans... maps or diagrams shall be posted at all shaft stations and in underground shops, lunchrooms, and...

  12. Amplitude modulation control of escape from a potential well

    International Nuclear Information System (INIS)

    Chacón, R.; Martínez García-Hoz, A.; Miralles, J.J.; Martínez, P.J.

    2014-01-01

    We demonstrate the effectiveness of periodic amplitude modulations in controlling (suppressing and enhancing) escape from a potential well through the universal model of a damped Helmholtz oscillator subjected to an external periodic excitation (the escape-inducing excitation) whose amplitude is periodically modulated (the escape-controlling excitation). Analytical and numerical results show that this multiplicative control works reliably for different subharmonic resonances between the two periodic excitations involved, and that its effectiveness is comparable to those of different methods of additive control. Additionally, we demonstrate the robustness of the multiplicative control against the presence of low-intensity Gaussian noise. -- Highlights: •Multiplicative control of escape from a potential well has been demonstrated. •Theoretical predictions are obtained from a Melnikov analysis. •It has been shown the robustness of the multiplicative control against noise.

  13. Escape panels in trawls – a consistent management tool?

    DEFF Research Database (Denmark)

    Krag, Ludvig Ahm; Herrmann, Bent; Feekings, Jordan P.

    2016-01-01

    ), saithe (Pollachius virens), haddock (Melanogrammus aeglefinus), plaice (Pleuronectes platessa) and Norway lobster (Nephrops norvegicus). Thus the modification by fishers of certain gear properties not specified in the legislation can significantly influence the efficiency of an escape panel. We discuss...

  14. Major features of immunesenescence, including reduced thymic output, are ameliorated by high levels of physical activity in adulthood.

    Science.gov (United States)

    Duggal, Niharika Arora; Pollock, Ross D; Lazarus, Norman R; Harridge, Stephen; Lord, Janet M

    2018-04-01

    It is widely accepted that aging is accompanied by remodelling of the immune system including thymic atrophy and increased frequency of senescent T cells, leading to immune compromise. However, physical activity, which influences immunity but declines dramatically with age, is not considered in this literature. We assessed immune profiles in 125 adults (55-79 years) who had maintained a high level of physical activity (cycling) for much of their adult lives, 75 age-matched older adults and 55 young adults not involved in regular exercise. The frequency of naïve T cells and recent thymic emigrants (RTE) were both higher in cyclists compared with inactive elders, and RTE frequency in cyclists was no different to young adults. Compared with their less active counterparts, the cyclists had significantly higher serum levels of the thymoprotective cytokine IL-7 and lower IL-6, which promotes thymic atrophy. Cyclists also showed additional evidence of reduced immunesenescence, namely lower Th17 polarization and higher B regulatory cell frequency than inactive elders. Physical activity did not protect against all aspects of immunesenescence: CD28 -ve CD57 +ve senescent CD8 T-cell frequency did not differ between cyclists and inactive elders. We conclude that many features of immunesenescence may be driven by reduced physical activity with age. © 2018 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  15. Development of donor-derived thymic lymphomas after allogeneic bone marrow transplantation in AKR/J mice

    International Nuclear Information System (INIS)

    Yasumizu, R.; Hiai, H.; Sugiura, K.

    1988-01-01

    The transplantation of bone marrow cells from BALB/c (but not C57BL/6 and C3H/HeN) mice was observed to lead to the development of thymic lymphomas (leukemias) in AKR/J mice. Two leukemic cell lines, CAK1.3 and CAK4.4, were established from the primary culture of two thymic lymphoma, and surface phenotypes of these cell lines found to be H-2d and Thy-1.2+, indicating that these lymphoma cells are derived from BALB/c donor bone marrow cells. Further analyses of surface markers revealed that CAK1.3 is L3T4+ Lyt2+ IL2R-, whereas CAK4.4 is L3T4- Lyt2- IL2R+. Both CAK1.3 and CAK4.4 were transplantable into BALB/c but not AKR/J mice, further indicating that these cells are of BALB/c bone marrow donor origin. The cells were found to produce XC+-ecotropic viruses, but xenotropic and mink cell focus-forming viruses were undetectable. Inasmuch as thymic lymphomas are derived from bone marrow cells of leukemia-resistant BALB/c strain of mice under the allogeneic environment of leukemia-prone AKR/J mice, this animal model may serve as a useful tool not only for the analysis of leukemic relapse after bone marrow transplantation but also for elucidation of the mechanism of leukemogenesis

  16. GREEN PEA GALAXIES REVEAL SECRETS OF Lyα ESCAPE

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Huan; Wang, Junxian [CAS Key Laboratory for Research in Galaxies and Cosmology, Department of Astronomy, University of Science and Technology of China (China); Malhotra, Sangeeta; Rhoads, James E. [Arizona State University, School of Earth and Space Exploration (United States); Gronke, Max; Dijkstra, Mark [Institute of Theoretical Astrophysics, University of Oslo (Norway); Jaskot, Anne [Smith College, Northampton, MA (United States); Zheng, Zhenya, E-mail: yanghuan@mail.ustc.edu.cn, E-mail: huan.y@asu.edu, E-mail: Sangeeta.Malhotra@asu.edu, E-mail: James.Rhoads@asu.edu [Pontificia Universidad Católica de Chile, Santiago (Chile)

    2016-04-01

    We analyze archival Lyα spectra of 12 “Green Pea” galaxies observed with the Hubble Space Telescope, model their Lyα profiles with radiative transfer models, and explore the dependence of the Lyα escape fraction on various properties. Green Pea galaxies are nearby compact starburst galaxies with [O iii] λ5007 equivalent widths (EWs) of hundreds of Å. All 12 Green Pea galaxies in our sample show Lyα lines in emission, with an Lyα EW distribution similar to high-redshift Lyα emitters. Combining the optical and UV spectra of Green Pea galaxies, we estimate their Lyα escape fractions and find correlations between Lyα escape fraction and kinematic features of Lyα profiles. The escape fraction of Lyα in these galaxies ranges from 1.4% to 67%. We also find that the Lyα escape fraction depends strongly on metallicity and moderately on dust extinction. We compare their high-quality Lyα profiles with single H i shell radiative transfer models and find that the Lyα escape fraction anticorrelates with the derived H i column densities. Single-shell models fit most Lyα profiles well, but not the ones with the highest escape fractions of Lyα. Our results suggest that low H i column density and low metallicity are essential for Lyα escape and make a galaxy an Lyα emitter.

  17. comparison of clinical features and CT findings between atypical thymoma and thymic carcinoma

    International Nuclear Information System (INIS)

    Wang Xiangyang; Tan Ye; Chen Juan; Wei Jiahu; Pan Jishun; Du Jun; Zhou Cheng

    2011-01-01

    Objective: To investigate the differences and the similarities of clinical presentations and CT features between type B3 thymoma (atypical thymoma) and type C thymoma (thymic carcinoma) in the WHO classification of thymic epithelial tumors. Methods: Complete CT findings of thirty cases of type B3 and seventeen cases of type C thymic epithelial tumors confirmed by histopathology according to WHO 2004 Classification System and clinical features including the prognosis of each case were reviewed retrospectively. Statistical analyses of the data for the age and the long diameter were performed with Independent-Samples t test between the two groups. Statistical analysis for gender, association with myasthenia gravis, method of the operation, contours, shapes, calcification,necrosis, enhancement pattern of the tumors on CT, presence of mediastinal lymphadenopathy, invasion of mediastinal fat, chest wall, pericardium, great vessel, pleural mediastinum, metastasis to the plural, pleural effusion, distant metastasis were performed with Fisher exact test. Kaplan-Meier method was employed for survival analysis. Results: Clinical data: the average age of type B3 group was significantly younger (t=-2.905, P=0.006). 90.0% (27/30) of patients in type B3 group were complicated by myasthenia gravis, while only 5.9% (1/17) of patients in type C group were complicated by myasthenia gravis. The difference between the two groups was statistically significant (P=0.000). The ratio of complete resection of type B3 group (80.0%) was significantly higher than that in type C group (P=0.001), 70.6% (12/17) of patients in type C group died within 2 years after surgical resection, while only 20.0% (6/30) of patients in type B3 group died within one to nine years after surgical resection. Three years' survival ratio of C group was 29.4%, and five years' survival ratio of C group was lower than 14.7%, which was significantly lower than B3 group five years' survival ratio was 94.7%), which was

  18. The influence of panic on the efficiency of escape

    Science.gov (United States)

    Shen, Jia-Quan; Wang, Xu-Wen; Jiang, Luo-Luo

    2018-02-01

    Whenever we (such as pedestrians) perceive a high density or imminent danger in a confined space, we tend to be panic, which can lead to severe injuries even in the absence of real dangers. Although it is difficult to measure panics in real conditions, we introduced a simple model to study the collective behaviors in condition of fire with dense smoke. Owing to blocking the sight with dense smoke, pedestrians in this condition have two strategies to escape: random-walking or walking along the wall. When the pedestrians are in moderate panic that mean the two types of behaviors are mixed(random-walking and walking along the wall). Our simulation results show that moderate panic, meaning that two escape strategies are mixed, reduces the escape time. In addition, the results indicate that moderate panic can improve the efficiency of escape, this theory also can be useful in a real escape situation. We hope that our research provides the theoretical understanding of underlying mechanisms of panic escape in the condition of poor sight.

  19. Negative Leadership

    Science.gov (United States)

    2013-03-01

    Negative Leadership by Colonel David M. Oberlander United States Army United States Army War...SUBTITLE Negative Leadership 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Colonel David M...Dr. Richard C. Bullis Department of Command Leadership , and Management 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING

  20. Negative liability

    NARCIS (Netherlands)

    Dari-Mattiacci, G.

    2009-01-01

    Negative and positive externalities pose symmetrical problems to social welfare. The law internalizes negative externalities by providing general tort liability rules. According to such rules, those who cause harm to others should pay compensation. In theory, in the presence of positive

  1. Negative ... concord?

    NARCIS (Netherlands)

    Giannakidou, A

    The main claim of this paper is that a general theory of negative concord (NC) should allow for the possibility of NC involving scoping of a universal quantifier above negation. I propose that Greek NC instantiates this option. Greek n-words will be analyzed as polarity sensitive universal

  2. A human thymic epithelial cell culture system for the promotion of lymphopoiesis from hematopoietic stem cells.

    Science.gov (United States)

    Beaudette-Zlatanova, Britte C; Knight, Katherine L; Zhang, Shubin; Stiff, Patrick J; Zúñiga-Pflücker, Juan Carlos; Le, Phong T

    2011-05-01

    A human thymic epithelial cell (TEC) line expressing human leukocyte antigen-ABC and human leukocyte antigen-DR was engineered to overexpress murine Delta-like 1 (TEC-Dl1) for the purpose of establishing a human culture system that supports T lymphopoiesis from hematopoietic progenitor cells (HPCs). Cord blood or bone marrow HPCs were co-cultured with either the parental TEC line expressing low levels of the Notch ligands, Delta-like 1 and Delta-like 4, or with TEC-Dl1 to determine if these cell lines support human lymphopoiesis. In co-cultures with cord blood or bone marrow HPCs, TEC-Dl1 cells promote de novo generation of CD7(pos)CD1a(pos) T-lineage committed cells. Most CD7(pos)CD1a(hi) cells are CD4(pos)CD8(pos) double-positive (DP). We found that TEC-Dl1 cells are insufficient to generate mature CD3(hi) CD4(pos) or CD3(hi) CD8(pos) single-positive (SP) T cells from the CD4(pos)CD8(pos) DP T cells; however, we detected CD3(lo) cells within the DP and SP CD4 and CD8 populations. The CD3(lo) SP cells expressed lower levels of interleukin-2Rα and interleukin-7Rα compared to CD3(lo) DP cells. In contrast to the TEC-Dl1 line, the parental TEC-84 line expressing low levels of human Notch ligands permits HPC differentiation to the B-cell lineage. We report for the first time a human TEC line that supports lymphopoiesis from cord blood and bone marrow HPC. The TEC cell lines described herein provide a novel human thymic stroma model to study the contribution of human leukocyte antigen molecules and Notch ligands to T-cell commitment and maturation and could be utilized to promote lymphopoiesis for immune cell therapy. Copyright © 2011 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

  3. Ion escape fluxes from the terrestrial high-latitude ionosphere

    International Nuclear Information System (INIS)

    Barakat, A.R.; Schunk, R.W.; Moore, T.E.; Waite, J.H. Jr.

    1987-01-01

    The coupled continuity and momentum equations for H + , O + , and electrons were solved for the terrestrial ionosphere in order to determine the limiting ion escape fluxes at high latitudes. The effects of solar cycle, season, geomagnetic activity, and the altitude of the acceleration region on the ion escape fluxes were studied for average conditions. In addition, a systematic parameter study was conducted to determine the extent to which variations in ionospheric conditions (for example, electron temperature, ion temperature, induced vertical ion drifts, etc.) can affect the results. The main conclusions of the study are as follows: (1) as solar activity increases, the general trend is for an increase in the limiting O + escape flux and a decrease in the limiting H + escape flux; (2) in winter the limiting escape fluxes of both O + and H + are larger than those in summer, particularly for low geomagnetic activity; (3) the O + content of the ion outflow increases with increasing ''demand'' imposed on the ionosphere by a high-altitude acceleration process, with increasing solar activity, with increasing geomagnetic activity, with increasing solar elevation from winter to summer, and with a lowering of the altitude of the acceleration region; (4) when H + is in a near-diffusive equilibrium state and a selective mechanism accelerates O + , the limiting O + escape flux is significantly reduced compared to that obtained when an H + outflow also occurs; and (5) at a given time or location the general trends described above can be significantly modified or even reversed owing to natural variations of the ionospheric ion and electron temperatures, induced vertical ion drifts, etc. The general trends obtained for average conditions appear to mimic the qualitative behavior determined from statistically averaged data for comparable absolute escape flux magnitudes

  4. Generation of mature T cells from human hematopoietic stem and progenitor cells in artificial thymic organoids.

    Science.gov (United States)

    Seet, Christopher S; He, Chongbin; Bethune, Michael T; Li, Suwen; Chick, Brent; Gschweng, Eric H; Zhu, Yuhua; Kim, Kenneth; Kohn, Donald B; Baltimore, David; Crooks, Gay M; Montel-Hagen, Amélie

    2017-05-01

    Studies of human T cell development require robust model systems that recapitulate the full span of thymopoiesis, from hematopoietic stem and progenitor cells (HSPCs) through to mature T cells. Existing in vitro models induce T cell commitment from human HSPCs; however, differentiation into mature CD3 + TCR-αβ + single-positive CD8 + or CD4 + cells is limited. We describe here a serum-free, artificial thymic organoid (ATO) system that supports efficient and reproducible in vitro differentiation and positive selection of conventional human T cells from all sources of HSPCs. ATO-derived T cells exhibited mature naive phenotypes, a diverse T cell receptor (TCR) repertoire and TCR-dependent function. ATOs initiated with TCR-engineered HSPCs produced T cells with antigen-specific cytotoxicity and near-complete lack of endogenous TCR Vβ expression, consistent with allelic exclusion of Vβ-encoding loci. ATOs provide a robust tool for studying human T cell differentiation and for the future development of stem-cell-based engineered T cell therapies.

  5. Immunologic mechanism of the suppressive effect of low dose radiation on thymic lymphoma induced by radiation

    International Nuclear Information System (INIS)

    Li Xiujuan; Yang Ying; Li Xiuyi; Liu Shuzheng

    1999-01-01

    To study immunologic mechanism of the suppressive effect of low dose radiation (LDR) on thymic lymphoma (TL) induced by high dose radiation (HDR). The authors adopted the model that C57BL/6J mice were administered whole body irradiation with 1.75 Gy X-rays one time every week for 4 weeks to induce TL. It was examined that splenic NK cytotoxic activity, IL-2 and γ-IFN secretion activity, peritoneal macrophage phagocytosis and its TNF-α secretion activity in mice with different dose 1 month after irradiation. The results showed that all the immunologic functions mentioned above in mice given 75 mGy 12 h before 1.75 Gy every time were higher than that in mice given only 1.75 Gy, and approached to the sham-irradiation mice. It suggested that the suppressive effect of LDR on TL induced by HDR may be related to the adaptive response induced by LDR and decreasing immunological functions damage caused by HDR

  6. Lineage Tracing and Cell Ablation Identify a Post-Aire-Expressing Thymic Epithelial Cell Population

    Directory of Open Access Journals (Sweden)

    Todd C. Metzger

    2013-10-01

    Full Text Available Thymic epithelial cells in the medulla (mTECs play a critical role in enforcing central tolerance through expression and presentation of tissue-specific antigens (TSAs and deletion of autoreactive thymocytes. TSA expression requires autoimmune regulator (Aire, a transcriptional activator present in a subset of mTECs characterized by high CD80 and major histocompatibility complex II expression and a lack of potential for differentiation or proliferation. Here, using an Aire-DTR transgenic line, we show that short-term ablation specifically targets Aire+ mTECs, which quickly undergo RANK-dependent recovery. Repeated ablation also affects Aire− mTECs, and using an inducible Aire-Cre fate-mapping system, we find that this results from the loss of a subset of mTECs that showed prior expression of Aire, maintains intermediate TSA expression, and preferentially migrates toward the center of the medulla. These results clearly identify a distinct stage of mTEC development and underscore the diversity of mTECs that play a key role in maintaining tolerance.

  7. Thymic repopulation following intrathymic injection of mouse bone marrow cells in MHC matched and mismatched recipients

    International Nuclear Information System (INIS)

    Chervenak, R.

    1986-01-01

    T cell precursors (pre-T cells) have traditionally been detected by their ability to repopulate the thymus of heavily irradiated mice following intravenous injection. Recently, Goldschneider et. al. developed an assay system which involves the direct injection of pre-T cells into the thymus. The authors used this technique to evaluate the ability of bone marrow cells to repopulate thymuses in various donor-host strain combinations. Sub-lethally irradiated (600R) mice were injected intrathymically with 2 x 10 6 bone marrow cells which differed from the recipient with respect to their Thy 1 allotype. The percentage of thymus cells expressing either the donor or recipient type Thy 1 marker was determined 14 to 21 days after injection. These experiments showed that in MHC matched donor-host combinations (AKR/cum → AKR/J and CBA/J → AKR/J), cells derived from the donor inoculum accounted for 40% to 75% of the total thymus population. MHC mismatched donor-host combinations (C57BL/6J → AKR/J and Balb/c → AKR/J) resulted in significantly less donor-type repopulation of the thymus. In these cases, donor repopulation typically ranged from 0% to 4%. The ability of the pre-T cells detected by intrathymic injection to proliferate in the thymic environment, therefore, appears to be influenced by the MHC. This may reflect commitment of pre-T cells to MHC haplotype recognition prior to their migration to the thymus

  8. Multiple Functions of the New Cytokine-Based Antimicrobial Peptide Thymic Stromal Lymphopoietin (TSLP

    Directory of Open Access Journals (Sweden)

    Louise Bjerkan

    2016-07-01

    Full Text Available Thymic stromal lymphopoietin (TSLP is a pleiotropic cytokine, hitherto mostly known to be involved in inflammatory responses and immunoregulation. The human tslp gene gives rise to two transcription and translation variants: a long form (lfTSLP that is induced by inflammation, and a short, constitutively-expressed form (sfTSLP, that appears to be downregulated by inflammation. The TSLP forms can be produced by a number of cell types, including epithelial and dendritic cells (DCs. lfTSLP can activate mast cells, DCs, and T cells through binding to the lfTSLP receptor (TSLPR and has a pro-inflammatory function. In contrast, sfTSLP inhibits cytokine secretion of DCs, but the receptor mediating this effect is unknown. Our recent studies have demonstrated that both forms of TSLP display potent antimicrobial activity, exceeding that of many other known antimicrobial peptides (AMPs, with sfTSLP having the strongest effect. The AMP activity is primarily mediated by the C-terminal region of the protein and is localized within a 34-mer peptide (MKK34 that spans the C-terminal α-helical region in TSLP. Fluorescent studies of peptide-treated bacteria, electron microscopy, and liposome leakage models showed that MKK34 exerted membrane-disrupting effects comparable to those of LL-37. Expression of TSLP in skin, oral mucosa, salivary glands, and intestine is part of the defense barrier that aids in the control of both commensal and pathogenic microbes.

  9. Myc contribution to γ-ray induced thymic lymphomas in mice of different genetic predispositions

    International Nuclear Information System (INIS)

    Sato, Toshihiro

    2008-01-01

    Myc gene has been suggested to be one of radiation targets in early genesis of γ ray-induced thymic lymphoma where Myc trisomy often occurs, and Myc activation results in p53 activation and apoptosis. The purpose of this study is to see the effects of radiation and mutation on Myc activation in the mouse. The lymphoma was induced by a single exposure of 3 Gy γ ray in BALB/c Bcl11b/Rit+/- and MSM p53-/- mice at 4 weeks after birth and by 4 weekly exposures of 2.5 Gy in p53+/- mouse. Genetic allele analysis for trisomy identification in the lymphoma was done by quantitative PCR using brain DNA as a control. Myc trisomy was found in the lymphoma of p53+/- mouse in 62% (23/37 animals) and of p53+/+, 66% (23/25), a similar frequency, suggesting that the target of radiation was not only the Myc activation. In addition, Myc trisomy frequency was 15% (4/27) in the lymphoma of Bcl11b+/+p53+/- and 36% (9/25), in heterozygote Bcl11b+/-. This finding suggested that the functional failure of Bcl11b reduced the contribution of Myc trisomy to the genesis. It was concluded that contribution of Myc trisomy to genesis of the lymphoma was dependent on genetic predisposition, and Myc-activated-, Bcl11b/Rit1-signal pathways played a parallel role in the genesis. (R.T.)

  10. Impaired Thymic Output in Patients with Chronic Hepatitis C Virus Infection

    DEFF Research Database (Denmark)

    Hartling, Hans Jakob; Gaardbo, Julie Christine; Ronit, Andreas

    2013-01-01

    Altered T cell homeostasis in chronic hepatitis C virus (HCV) infection has been demonstrated. However, it is unknown if fibrosis is associated with more perturbed T cell homeostasis in chronic HCV infection. The aim of the present study was to examine and compare T cell subsets including recent...... thymic emigrants (RTE), naive, memory, senescent, apoptotic and IL-7 receptor α (CD127) expressing CD4+ and CD8+ T cells as well as telomere length and interferon-γ production in HCV-infected patients with (n=25) and without (n=26) fibrosis as well as in healthy controls (n=24). Decreased proportions...... of CD4+ and CD8+ RTE were found in HCV-infected patients, especially in HCV-infected patients with fibrosis (14.3% (9.7-23.0) and 28.8% (16.1-40.5), respectively) compared to healthy controls (24.2% (16.3-32.1), P=0.004, and 39.1% (31.6-55.0), P=0.010, respectively). Furthermore, HCV-infected patients...

  11. PRESENCE OF THYMIC TISSUE IN THE ANTERIOR MEDIASTINAL FATTY TISSUE AND ITS SIGNIFICANCE IN THYMECTOMY FOR MYASTHENIA GRAVIS PATIENT: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Athouba

    2016-03-01

    Full Text Available In 1970s, presence of thymic tissue in anterior mediastinal adipose tissue around the thymus was found. Here we report a case of ectopic thymic tissue in the mediastinum and the possible relevance of this distribution of thymic tissue outside thymus to the therapeutic yield of thymectomies in myasthenia gravis. A 30-year lady with myasthenia gravis (nonthymomatous presented with difficulty in swallowing and breathing for the last 1 years. She was under medical treatment but with little improvement. She underwent extended thymectomy, after which an en bloc resection of the anterior mediastinal fat tissues from pericardium and pleura, including the thymus, was performed. Grossly the soft tissue specimen taken from near left lateral area of heart was fibrofatty tissue. Microscopically isolated thymic tissues were seen interspersed among the fatty tissues composed of mature lymphocytes, epithelial cells and few Hassall's corpuscles were observed. Thymus specimen was within normal histological limits. To ensure complete removal, the adipose tissue at the anterior mediastinum as well as the gross thymus should be removed. Thymic tissue incidence in individual locations was as follows: Retrothyroid, 3(6%; peritracheal, 5 (10%; retrotracheal, 1 (2%; right phrenic nerve, 2 (4%; left phrenic nerve, 14 (28%; right recurrent laryngeal nerve, 2 (4%; left recurrent laryngeal nerve, 2 (4% and periaortic, 0. Trans-sternal thymectomy was found to be beneficial to all patients of mild-to-moderate myasthenia gravis with 70.2% patients showing improvement postoperatively.

  12. To run or hide?: escape behaviour in a cryptic African snake | Maritz ...

    African Journals Online (AJOL)

    Optimal escape theory predicts that escape behaviour of an organism is best understood in terms of costs and benefits of escaping relative to risk of predation. However, risk of predation facing an organism is dependent on various biotic and abiotic factors. In order to better understand escape behaviour of an African snake, ...

  13. Improving escape panel selectivity in Nephrops directed fisheries by actively stimulating fish behaviour

    DEFF Research Database (Denmark)

    Krag, Ludvig Ahm; Herrmann, Bent; Feekings, Jordan P.

    2017-01-01

    The efficiency of escape panels inserted in trawls relies on fish actively attempting to escape through them. However, several studies indicate that most fish drift towards the aft end of the trawl, passing the escape panel through which they easily could have escaped, without making contact with...

  14. [Negative hallucination, self-onsciousness and ageing].

    Science.gov (United States)

    Hazif-Thomas, C; Stephan, F; Walter, M; Thomas, P

    2015-04-01

    Negative hallucinations are characterized by a defect in perception of an object or a person, or a denial of the existence of their perception. Negative hallucinations create blank spaces, due to both an impossible representation and an incapability of investment in reality. They have a close relationship with Cotard's syndrome, delusional theme of organ denial observed in melancholic syndromes in the elderly. Phenomenological approach. The phenomenology of negative hallucinations provides quite an amount of information on the origin of the psychotic symptoms when one is rather old. The connections between hallucinations, mood disorders and negative symptoms are often difficult to live with for the nearest and dearest. Negative hallucinations require a strict approach to identify their expression that is crucial because a wide heterogeneity exists within the pathological pictures, as in Cotard's syndrome. Although the negative hallucination has an anti traumatic function in elderly people fighting against mental pain, it still represents a deficiency in symbolization. The prevalence of this symptom is without doubt underestimated, although its presence often underlines thymic suffering that is more striking. These hallucinatory symptoms have an important impact on the patients' daily life, and they appear to be prisoners of a suffering, which cannot be revealed. We propose in this article to review the clinical symptoms of negative hallucinations in the elderly and the way to manage them. The medicinal approaches are not always effective. A greater place must be given to what is in connection with the body, aiming at a strong impact and thus to offer non-pharmacological approaches, such as somatic ones, which can be either invasive (electroconvulsive therapy) or not (transcranial magnetic stimulation). Copyright © 2014. Published by Elsevier Masson SAS.

  15. THE ESCAPE FRACTION OF IONIZING RADIATION FROM GALAXIES

    International Nuclear Information System (INIS)

    Benson, Andrew; Venkatesan, Aparna; Shull, J. Michael

    2013-01-01

    The escape of ionizing radiation from galaxies plays a critical role in the evolution of gas in galaxies, and the heating and ionization history of the intergalactic medium. We present semi-analytic calculations of the escape fraction of ionizing radiation for both hydrogen and helium from galaxies ranging from primordial systems to disk-type galaxies that are not heavily dust-obscured. We consider variations in the galaxy density profile, source type, location, and spectrum, and gas overdensity/distribution factors. For sufficiently hard first-light sources, the helium ionization fronts closely track or advance beyond that of hydrogen. Key new results in this work include calculations of the escape fractions for He I and He II ionizing radiation, and the impact of partial ionization from X-rays from early active galactic nuclei or stellar clusters on the escape fractions from galaxy halos. When factoring in frequency-dependent effects, we find that X-rays play an important role in boosting the escape fractions for both hydrogen and helium, but especially for He II. We briefly discuss the implications of these results for recent observations of the He II reionization epoch at low redshifts, as well as the UV data and emission-line signatures from early galaxies anticipated from future satellite missions.

  16. THE ESCAPE FRACTION OF IONIZING RADIATION FROM GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Andrew [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Venkatesan, Aparna [Department of Physics and Astronomy, University of San Francisco, San Francisco, CA 94117 (United States); Shull, J. Michael, E-mail: abenson@obs.carnegiescience.edu, E-mail: avenkatesan@usfca.edu, E-mail: michael.shull@colorado.edu [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309 (United States)

    2013-06-10

    The escape of ionizing radiation from galaxies plays a critical role in the evolution of gas in galaxies, and the heating and ionization history of the intergalactic medium. We present semi-analytic calculations of the escape fraction of ionizing radiation for both hydrogen and helium from galaxies ranging from primordial systems to disk-type galaxies that are not heavily dust-obscured. We consider variations in the galaxy density profile, source type, location, and spectrum, and gas overdensity/distribution factors. For sufficiently hard first-light sources, the helium ionization fronts closely track or advance beyond that of hydrogen. Key new results in this work include calculations of the escape fractions for He I and He II ionizing radiation, and the impact of partial ionization from X-rays from early active galactic nuclei or stellar clusters on the escape fractions from galaxy halos. When factoring in frequency-dependent effects, we find that X-rays play an important role in boosting the escape fractions for both hydrogen and helium, but especially for He II. We briefly discuss the implications of these results for recent observations of the He II reionization epoch at low redshifts, as well as the UV data and emission-line signatures from early galaxies anticipated from future satellite missions.

  17. Low thymic output in the 22q11.2 deletion syndrome measured by CCR9+CD45RA+ T cell counts and T cell receptor rearrangement excision circles

    DEFF Research Database (Denmark)

    Lima, K; Abrahamsen, Gitte Meldgaard; Foelling, I

    2010-01-01

    Thymic hypoplasia is a frequent feature of the 22q11.2 deletion syndrome, but we know little about patients' age-related thymic output and long-term consequences for their immune system. We measured the expression of T cell receptor rearrangement excision circles (TREC) and used flow cytometry...

  18. Passive Facebook use, Facebook addiction, and associations with escapism: an experimental vignette study

    OpenAIRE

    Young, LN; Kuss, DJ; Griffiths, MD; Howard, CJ

    2017-01-01

    There is relatively little research considering motivations of passive Facebook use. However, research regarding motivations of general Facebook use indicates that people use Facebook to escape – and that escapism may motivate passive Facebook use. Research also suggests that using Facebook to escape is associated with Facebook addiction. Using an experimental vignette design, the present research investigated whether passive Facebook use is motivated by escapism and whether this escape motiv...

  19. An anticipative escape system for vehicles in water crashes

    Science.gov (United States)

    Shen, Chuanliang; Wang, Jiawei; Yin, Qi; Zhu, Yantao; Yang, Jiawei; Liao, Mengdi; Yang, Liming

    2017-07-01

    In this article, it designs an escape system for vehicles in water crashes. The structure mainly contains sensors, control organs and actuating mechanism for both doors and windows. Sensors judge whether the vehicle falls into water or is in the falling process. The actuating mechanism accepts the signal delivered by the control organs, then open the electronic central lock on doors and meanwhile lower the window. The water escape system is able to anticipate drowning situations for vehicles and controls both doors and windows in such an emergency. Under the premise of doors staying in an undamaged state, it is for sure that people in the vehicle can open the door while drowning in the water and safely escape.

  20. Escaping and Falling into Poverty in India Today.

    Science.gov (United States)

    Thorat, Amit; Vanneman, Reeve; Desai, Sonalde; Dubey, Amaresh

    2017-05-01

    The study examines the dynamic nature of movements into and out of poverty over a period when poverty has fallen substantially in India. The analysis identifies people who escaped poverty and those who fell into it over the period 2005 to 2012. The analysis identifies people who escaped poverty and those who fell into it over the period 2005 to 2012. Using panel data from the India Human Development Survey for 2005 and 2012, we find that the risks of marginalized communities such as Dalits and Adivasis of falling into or remaining in poverty were higher than those for more privileged groups. Some, but not all of these higher risks are explained by educational, financial, and social disadvantages of these groups in 2005. Results from a logistic regression show that some factors that help people escape poverty differ from those that push people into it and that the strength of their effects varies.

  1. Escape response of planktonic protists to fluid mechanical signals

    DEFF Research Database (Denmark)

    Jakobsen, Hans Henrik

    2001-01-01

    The escape response to fluid mechanical signals was examined in 6 protists, 4 ciliates and 2 dinoflagellates. When exposed to a siphon flow. 3 species of ciliates, Balanion comatum, Strobilidium sp., and Mesodinium pulex, responded with escape jumps. The threshold deformation rates required...... times lower than that of a non-jumping similar sized protist when the predator was Temora longicornis, which captures prey entrained in a feeding current. However, when the predator was the ambush- feeding copepod Acartia tonsa, the predation mortalities of jumping and non-jumping protists were...... of similar magnitude. Escape responses may thus be advantageous in some situations. However, jumping behaviour may also enhance susceptibility to some predators, explaining the different predator avoidance strategies (jumping or not) that have evolved in planktonic protists....

  2. Isolated thymic Langerhans cell histiocytosis discovered on F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT).

    Science.gov (United States)

    Turpin, Sophie; Carret, Anne-Sophie; Dubois, Josée; Buteau, Chantal; Patey, Natalie

    2015-11-01

    The thymic infiltration in young patients with multisystemic Langerhans cell histiocytosis and its radiologic features are well known. However, isolated thymic disease has seldom been reported in the literature. We report the case of a 10-month-old child admitted for fever of unknown origin. Whole-body F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) was performed to identify a focus of infection. It demonstrated an unusual aspect of the thymus, which led to further investigation and revealed isolated infiltration of the thymus by Langerhans cell histiocytosis. The patient was treated accordingly and is now disease free. As evaluation of Langerhans cell histiocytosis patients with F-18 FDG PET/CT is becoming more frequent, it is important to be aware of the scintigraphical characteristics of thymic Langerhans cell histiocytosis.

  3. Isolated thymic Langerhans cell histiocytosis discovered on F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT)

    Energy Technology Data Exchange (ETDEWEB)

    Turpin, Sophie [CHU Sainte-Justine, Nuclear Medicine, Montreal (Canada); Carret, Anne-Sophie [CHU Sainte-Justine, Hemato-Oncology, Montreal (Canada); Dubois, Josee [CHU Sainte-Justine, Radiology, Montreal (Canada); Buteau, Chantal [CHU Sainte-Justine, Infectious Diseases, Montreal (Canada); Patey, Natalie [CHU Sainte-Justine, Pathology, Montreal (Canada)

    2015-11-15

    The thymic infiltration in young patients with multisystemic Langerhans cell histiocytosis and its radiologic features are well known. However, isolated thymic disease has seldom been reported in the literature. We report the case of a 10-month-old child admitted for fever of unknown origin. Whole-body F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) was performed to identify a focus of infection. It demonstrated an unusual aspect of the thymus, which led to further investigation and revealed isolated infiltration of the thymus by Langerhans cell histiocytosis. The patient was treated accordingly and is now disease free. As evaluation of Langerhans cell histiocytosis patients with F-18 FDG PET/CT is becoming more frequent, it is important to be aware of the scintigraphical characteristics of thymic Langerhans cell histiocytosis. (orig.)

  4. Early thymic T cell development in young transgenic mice overexpressing human Cu/Zn superoxide dismutase, a model of Down syndrome.

    Science.gov (United States)

    Laurent, Julien; Paly, Evelyne; Marche, Patrice N; London, Jacqueline

    2006-06-01

    Previous studies have shown that transgenic mice overexpressing Cu/Zn superoxide dismutase, a model of Down syndrome, exhibit premature thymic involution. We have performed a flow cytometry analysis of the developing thymus in these homozygous transgenic mice (hSOD1/hSOD1: Tg-SOD). Longitudinal follow-up analysis from day 3 to day 280 showed an early thymic development in Tg-SOD mice compared with controls. This early thymic development was associated with an increased migration of mature T cells to peripheral lymphoid organs. BrdU labeling showed no difference between Tg-SOD and control mice, confirming that the greater number of peripheral T cells in Tg-SOD mice was not due to extensive proliferation of these cells but rather to a greater pool of emigrant T cells in Tg-SOD.

  5. Catch me if you can: Leukemia Escape after CD19-Directed T Cell Immunotherapies

    Directory of Open Access Journals (Sweden)

    Marco Ruella

    2016-01-01

    Full Text Available Immunotherapy is the revolution in cancer treatment of this last decade. Among multiple approaches able to harness the power of the immune system against cancer, T cell based immunotherapies represent one of the most successful examples. In particular, biotechnological engineering of protein structures, like the T cell receptor or the immunoglobulins, allowed the generation of synthetic peptides like chimeric antigen receptors and bispecific antibodies that are able to redirect non-tumor specific T cells to recognize and kill leukemic cells. The anti-CD19/CD3 bispecific antibody blinatumomab and anti-CD19 chimeric antigen receptor T cells (CART19 have produced deep responses in patients with relapsed and refractory B-cell acute leukemias. However, although the majority of these patients responds to anti-CD19 immunotherapy, a subset of them still relapses. Interestingly, a novel family of leukemia escape mechanisms has been described, all characterized by the apparent loss of CD19 on the surface of leukemic blasts. This extraordinary finding demonstrates the potent selective pressure of CART19/blinatumomab that drives extreme and specific escape strategies by leukemic blasts. Patients with CD19-negative relapsed leukemia have very poor prognosis and novel approaches to treat and ideally prevent antigen-loss are direly needed. In this review we discuss the incidence, mechanisms and therapeutic approaches for CD19-negative leukemia relapses occuring after CD19-directed T cell immunotherapies and present our future perspective.

  6. Negative CO

    NARCIS (Netherlands)

    Meysman, F.J.R.; Montserrat, F.

    2017-01-01

    Negative emission technologies (NETs) target the removal of carbon dioxide (CO2) from the atmosphere, and are being actively investigated as a strategy to limit global warming to within the 1.5–2°C targets of the 2015 UN climate agreement. Enhanced silicate weathering (ESW) proposes to

  7. Negative Certainty

    Science.gov (United States)

    Ariso, José María

    2017-01-01

    The definitions of "negative knowledge" and the studies in this regard published to date have not considered the categorial distinction Wittgenstein established between knowledge and certainty. Hence, the important role that certainty, despite its omission, should have in these definitions and studies has not yet been shown. In this…

  8. Rapid endosomal escape of prickly nanodiamonds: implications for gene delivery

    Science.gov (United States)

    Chu, Zhiqin; Miu, Kaikei; Lung, Pingsai; Zhang, Silu; Zhao, Saisai; Chang, Huan-Cheng; Lin, Ge; Li, Quan

    2015-06-01

    The prickly nanodiamonds easily entered cells via endocytosis followed by unique intracellular translocation characteristics—quick endosomal escape followed by stable residence in cytoplasm. Endosomal membrane rupturing is identified as the major route of nanodiamonds’ escaping the vesicle confinement and to the cytoplasm. Little cytotoxicity is observed to associate with the nanodiamonds’ cytosolic release. Such features enable its application for gene delivery, which requires both effective cellular uptake and cytosolic release of the gene. Taking green fluorescent protein gene as an example, we demonstrate the successful cytosolic delivery and expression of such a gene using the prickly nanodiamonds as carrier.

  9. Rapid endosomal escape of prickly nanodiamonds: implications for gene delivery

    Science.gov (United States)

    Chu, Zhiqin; Miu, Kaikei; Lung, Pingsai; Zhang, Silu; Zhao, Saisai; Chang, Huan-Cheng; Lin, Ge; Li, Quan

    2015-01-01

    The prickly nanodiamonds easily entered cells via endocytosis followed by unique intracellular translocation characteristics—quick endosomal escape followed by stable residence in cytoplasm. Endosomal membrane rupturing is identified as the major route of nanodiamonds’ escaping the vesicle confinement and to the cytoplasm. Little cytotoxicity is observed to associate with the nanodiamonds’ cytosolic release. Such features enable its application for gene delivery, which requires both effective cellular uptake and cytosolic release of the gene. Taking green fluorescent protein gene as an example, we demonstrate the successful cytosolic delivery and expression of such a gene using the prickly nanodiamonds as carrier. PMID:26123532

  10. Rapid endosomal escape of prickly nanodiamonds: implications for gene delivery.

    Science.gov (United States)

    Chu, Zhiqin; Miu, Kaikei; Lung, Pingsai; Zhang, Silu; Zhao, Saisai; Chang, Huan-Cheng; Lin, Ge; Li, Quan

    2015-06-30

    The prickly nanodiamonds easily entered cells via endocytosis followed by unique intracellular translocation characteristics—quick endosomal escape followed by stable residence in cytoplasm. Endosomal membrane rupturing is identified as the major route of nanodiamonds' escaping the vesicle confinement and to the cytoplasm. Little cytotoxicity is observed to associate with the nanodiamonds' cytosolic release. Such features enable its application for gene delivery, which requires both effective cellular uptake and cytosolic release of the gene. Taking green fluorescent protein gene as an example, we demonstrate the successful cytosolic delivery and expression of such a gene using the prickly nanodiamonds as carrier.

  11. Bone marrow-derived thymic antigen-presenting cells determine self-recognition of Ia-restricted T lymphocytes

    International Nuclear Information System (INIS)

    Longo, D.L.; Kruisbeek, A.M.; Davis, M.L.; Matis, L.A.

    1985-01-01

    The authors previously have demonstrated that in radiation-induced bone marrow chimeras, T-cell self-Ia restriction specificity appeared to correlate with the phenotype of the bone marrow-derived antigen-presenting (or dendritic) cell in the thymus during T-cell development. However, these correlations were necessarily indirect because of the difficulty in assaying thymic function directly by adult thymus transplant, which has in the past been uniformly unsuccessful. They now report success in obtaining functional T cells from nude mice grafted with adult thymuses reduced in size by treatment of the thymus donor with anti-thymocyte globulin and cortisone. When (B10 Scn X B10.D2)F1 nude mice (I-Ab,d) are given parental B10.D2 (I-Ad) thymus grafts subcutaneously, their T cells are restricted to antigen recognition in association with I-Ad gene products but not I-Ab gene products. Furthermore, thymuses from (B10 X B10.D2)F1 (I-Ab,d)----B10 (I-Ab) chimeras transplanted 6 months or longer after radiation (a time at which antigen-presenting cell function is of donor bone marrow phenotype) into (B10 X B10.D2)F1 nude mice generate T cells restricted to antigen recognition in association with both I-Ad and I-Ab gene products. Thymuses from totally allogeneic bone marrow chimeras appear to generate T cells of bone marrow donor and thymic host restriction specificity. Thus, when thymus donors are radiation-induced bone marrow chimeras, the T-cell I-region restriction of the nude mice recipients is determined at least in part by the phenotype of the bone marrow-derived thymic antigen presenting cells or dendritic cells in the chimeric thymus

  12. Critical role for thymic CD19+CD5+CD1dhiIL-10+ regulatory B cells in immune homeostasis.

    Science.gov (United States)

    Xing, Chen; Ma, Ning; Xiao, He; Wang, Xiaoqian; Zheng, Mingke; Han, Gencheng; Chen, Guojiang; Hou, Chunmei; Shen, Beifen; Li, Yan; Wang, Renxi

    2015-03-01

    This study tested the hypothesis that besides the spleen, LNs, peripheral blood, and thymus contain a regulatory IL-10-producing CD19(+)CD5(+)CD1d(high) B cell subset that may play a critical role in the maintenance of immune homeostasis. Indeed, this population was identified in the murine thymus, and furthermore, when cocultured with CD4(+) T cells, this population of B cells supported the maintenance of CD4(+)Foxp3(+) Tregs in vitro, in part, via the CD5-CD72 interaction. Mice homozygous for Cd19(Cre) (CD19(-/-)) express B cells with impaired signaling and humoral responses. Strikingly, CD19(-/-) mice produce fewer CD4(+)Foxp3(+) Tregs and a greater percentage of CD4(+)CD8(-) and CD4(-)CD8(+) T cells. Consistent with these results, transfer of thymic CD19(+)CD5(+)CD1d(hi) B cells into CD19(-/-) mice resulted in significantly up-regulated numbers of CD4(+)Foxp3(+) Tregs with a concomitant reduction in CD4(+)CD8(-) and CD4(-)CD8(+) T cell populations in the thymus, spleen, and LNs but not in the BM of recipient mice. In addition, thymic CD19(+)CD5(+)CD1d(hi) B cells significantly suppressed autoimmune responses in lupus-like mice via up-regulation of CD4(+)Foxp3(+) Tregs and IL-10-producing Bregs. This study suggests that thymic CD19(+)CD5(+)CD1d(hi)IL-10(+) Bregs play a critical role in the maintenance of immune homeostasis. © Society for Leukocyte Biology.

  13. Clinical application of SPECT-CT with 99mTc-Tektrotyd in bronchial and thymic neuroendocrine tumors (NETs).

    Science.gov (United States)

    Sergieva, Sonya; Robev, Bozhil; Dimcheva, Milena; Fakirova, Albena; Hristoskova, Radka

    2016-01-01

    Neuroendocrine tumors (NETs) of the thorax including bronchial and thymic tumors belong to foregut NETs. Limited loco-regional thoracic NETs can be resected with surgery, but in extensive metastatic disease the treatment is mainly palliative. A high incidence and density of somatostatin receptors (SSTR2, SSTR3, and SSTR5) are found in thoracic NETs. The purpose of this study was to evaluate the role of SPECT-CT somatostatin receptor scintigraphy (SRS) with 99mTc-Tektrotyd for imaging, staging and follow up of patients with bronchial and thymic neuroendocrine tumors. Forty-one patients with thoracic tumors with neuroendocrine differentiation were studied. Sixty-eight examinations including SPECT-CT studies of the neck and chest and/or abdomen and pelvis were carried out 2-4 hrs. post i.v. administration of aver-age 740 MBq activity dose of 99mTc-EDDA/HYNIC-TOC (Tektrotyd, Polatom). In all 41 investigated patients we obtained 81.25% (13/16), 88% (22/25) and 85.36% (35/41) of sensitivity, specificity and accuracy of this diagnostic approach, respectively. Somatostatin-receptor scintigraphy correctly identified all primary NETs located in the lungs and thymus. SPECT-CT studies with 99mTc-EDDA/HYNIC-TOC resulted in exact pre-surgical and pre-treatment N/M staging of bronchial and thymic NETs, except 2 cases with multiple hepatic metastases and 1 with massive suprarenal metastasis. It can be concluded that SPECT-CT with 99mTc-EDDA/HYNIC-TOC is a valuable tool for staging and follow-up of patients with thoracic NETs.

  14. Tumor carcinóide do timo - Caso clínico Thymic carcinoid - case report

    Directory of Open Access Journals (Sweden)

    Lina Carvalho

    2010-01-01

    Full Text Available Os tumores neuroendócrinos primários representam cerca de 4% do total dos tumores do mediastino anterior, incluindo o timo, afectando mais homens que mulheres numa razão de 3:1 e apresentando uma maior incidência entre os 40 e os 60 anos. Antigamente classificados como timomas, desde 1972 são considerados um grupo distinto de neoplasias tímicas, podendo ser biologicamente activos, estando sobretudo associados à síndroma NEM-1 (19 a 25% dos doentes, sendo nestes casos mais agressivos. São descritos como tendo grande progressão local, recorrência e metástases em elevada percentagem de casos, o que determina um mau prognóstico. O estadiamento é o parâmetro mais importante para determinar a sobrevida. Tumores detectados em fase precoce e capsulados associam-se a um excelente prognóstico, enquanto em estádios avançados, localmente invasivos, têm prognóstico relativamente pobre. A remoção cirúrgica completa, para todos os tumores tímicos, é a base da terapêutica e o factor crítico para a sobrevivência a longo prazo, independentemente do tipo histológico. São uma causa de morte importante, nomeadamente os tumores associados a NEM-1 e síndroma de Cushing, e há autores que defendem a realização de timectomia profiláctica nestes doentes.Primary neuroendocrine tumours (carcinoid tumours account for about 4% of anterior mediastinal tumours concerning thymus localization. They appear to have a male predilection (3:1 ratio and occur mostly between 40 and 60 years of age. Classified primarily as thymomas, they have been considered a different group of thymic neoplasia since 1972. They can be biologically active, mostly associated with MEN-1 (19-25% of patients and more aggressive in these cases. As a locally invasive disease, with recurrence and metastasis in a high percentage of cases, it correlates with a poor prognosis. Staging is the most important determinant of survival. Encapsulated tumours diagnosed in early stages

  15. Differentiation of hematopoietic stem cells in irradiated mouse thymic lobes. Kinetics and phenotype of progeny

    International Nuclear Information System (INIS)

    Spangrude, G.J.; Scollay, R.

    1990-01-01

    To define cell populations which participate in the very early stages of T cell development in the mouse thymus, we enriched hematopoietic stem cells from mouse bone marrow and injected them into thymic lobes of irradiated Ly-5 congenic recipients. The progeny of the stem cells were identified and their phenotypes were determined by two-color flow cytometry for the expression of various cell surface differentiation Ag during the course of their subsequent intrathymic development. The majority of the differentiation which occurred in the first 10 days after intrathymic cell transfer was myeloid in nature; hence, this study demonstrates that the irradiated thymus is not strictly selective for T cell development. Further, the maximum rate of T cell development was observed after intrathymic injection of 200 stem cells. Donor-derived cells which did not express Ag characteristic of the myeloid lineage could be detected and their phenotypes could be determined by flow cytometry as early as 7 days after intrathymic injection. At this time, the cells were still very similar phenotypically to the bone marrow hematopoietic stem cells. Exceptions to this were the expression of stem cell Ag 2 and a decrease in the level of MHC class I Ag expression. After 9 days, the donor-derived cells expressed high levels of the Thy-1 Ag and proceeded to change in cell surface phenotype as differentiation continued. These cell phenotypes are described for the time frame ending 18 days after injection, when most donor-derived cells were phenotypically small CD4+ CD8+ (double-positive) thymocytes

  16. Thymic Stromal Lymphopoietin Attenuates the Development of Atherosclerosis in ApoE−/− Mice

    Science.gov (United States)

    Yu, Kunwu; Zhu, Pengfei; Dong, Qian; Zhong, Yucheng; Zhu, Zhengfeng; Lin, Yingzhong; Huang, Ying; Meng, Kai; Ji, Qingwei; Yi, Guiwen; Zhang, Wei; Wu, Bangwei; Mao, Yi; Cheng, Peng; Zhao, Xiaoqi; Mao, Xiaobo; Zeng, Qiutang

    2013-01-01

    Background Thymic stromal lymphopoietin (TSLP) is a cytokine with multiple effects on the body. For one thing, TSLP induces Th2 immunoreaction and facilitates allergic reaction; for another, it promotes the differentiation of naturally occurring CD4+CD25+Foxp3+ regulatory T cells (nTregs) and maintains immune tolerance. However, the exact role of TSLP in atherosclerosis remains unknown. Methods and Results In vitro, we examined the phenotype of TSLP‐conditioned bone marrow dendritic cells (TSLP‐DCs) of apolipoprotein E–deficient (ApoE−/−) mice and their capacity to induce the differentiation of Tregs. Our results indicated that TSLP‐DCs obtained the characteristics of tolerogenic dendritic cells and increased a generation of CD4+ latency‐associated peptide (LAP)+ Tregs and nTregs when cocultured with naive T cells. In addition, the functional relevance of TSLP and TSLP‐DCs in the development of atherosclerosis was also determined. Interestingly, we found that TSLP was almost absent in cardiovascular tissue of ApoE−/− mice, and TSLP administration increased the levels of antioxidized low‐density lipoprotein IgM and IgG1, but decreased the levels of IgG2a in plasma. Furthermore, mice treated with TSLP and TSLP‐DCs developed significantly fewer (32.6% and 28.2%, respectively) atherosclerotic plaques in the aortic root compared with controls, along with increased numbers of CD4+LAP+ Tregs and nTregs in the spleen and decreased inflammation in the aorta, which could be abrogated by anti‐TGF‐β antibody. Conclusions Our results revealed a protective role for TSLP in atherosclerosis that is possibly mediated by reestablishing a tolerogenic immune response, which may represent a novel possibility for treatment or prevention of atherosclerosis. PMID:23985377

  17. Treatment outcome of thymic epithelial tumor: prognostic factors and optimal postoperative radiation therapy

    International Nuclear Information System (INIS)

    Oh, Dong Ryul; Ahn, Yong Chan; Kim, Kwan Min; Kim, Jhin Gook; Shim, Young Mog; Han, Jung Ho

    2005-01-01

    This study was conducted to analyze treatment outcome and prognostic significance of World Health Organization (WHO)-defined thymic epithelial tumor (TET) subtype and to assess optimal radiation target volume in patients receiving surgery and adjuvant radiation therapy with TET. The record of 160 patients with TET, who received surgical resection at the Samsung medical Center, from December 1994 to June 2004, were reviewed. 99 patients were treated with postoperative radiation therapy (PORT). PORT was recommended when patients had more than one findings among suspicious incomplete resection or positive resection margin or Masaoka stage II ∼ IV or WHO tumor type B2 ∼ C. PORT performed to primary tumor bed only with a mean dose of 54 Gy. The prognostic factor and pattern of failure were analyzed retrospectively. The overall survival rate at 5 years was 87.3%. Age (more than 60 years 77.8%, less than 60 years 91.1%; ρ = 0.03), Masaoka stage (I 92.2%, II 95.4%, III 82.1%, IV 67.5%; ρ = 0.001), WHO tumor type (A-B1 96.0%, B2-C 82.3%; ρ = 0.001), Extent of resection (R0 resection 92.3%, R1 or 2 resection 72.6%; ρ = 0.001) were the prognostic factors according to univariate analysis. But WHO tumor type was the only significant prognostic factor according to multivariate analysis. Recurrence was observed in 5 patients of 71 Masoka stage I-III patients who received grossly complete tumor removal (R0, R1 resection ) and PORT to primary tumor bed. Mediastinal recurrence was observed in only one patients. There were no recurrence within irradiation field. WHO tumor type was the important prognostic factor to predict survival of patients with TET. This study suggest that PORT to only primary tumor bed was optimal. To avoid pleura-or pericardium-based recurrence, further study of effective chemotherapy should be investigated

  18. Thymic versus induced regulatory T cells – who regulates the regulators?

    Directory of Open Access Journals (Sweden)

    Giovanni Antonio Maria Povoleri

    2013-06-01

    Full Text Available Physiological health must balance immunological responsiveness against foreign pathogens with tolerance towards self-components and commensals. Disruption of this balance causes autoimmune diseases/chronic inflammation, in case of excessive immune responses, and persistent infection/immunodeficiency if regulatory components are overactive. This homeostasis occurs at two different levels: at a resting state to prevent autoimmune disease, as autoreactive effector T-cells (Teffs are only partially deleted in the thymus, and during inflammation to prevent excessive tissue injury, contract the immune response and enable tissue repair. Adaptive immune cells with regulatory function (regulatory T-cells are essential to control Teffs. Two sets of regulatory T cell are required to achieve the desired control: those emerging de novo from embryonic/neonatal thymus (thymic or tTregs, whose function is to control autoreactive Teffs to prevent autoimmune diseases, and those induced in the periphery (peripheral or pTregs to acquire regulatory phenotype in response to pathogens/inflammation. The differentiation mechanisms of these cells determine their commitment to lineage and plasticity towards other phenotypes. tTregs, expressing high levels of IL-2 receptor alpha chain (CD25, and the transcription factor Foxp3, are the most important, since mutations or deletions in these genes cause fatal autoimmune diseases in both mice and men. In the periphery, instead, Foxp3+ pTregs can be induced from naïve precursors in response to environmental signals. Here, we discuss molecular signatures and induction processes, mechanisms and sites of action, lineage stability and differentiating characteristics of both Foxp3+ and Foxp3- populations of regulatory T cells, derived from the thymus or induced peripherally. We relate these predicates to programs of cell-based therapy for the treatment of autoimmune diseases and induction of tolerance to transplants.

  19. Pre-thymic somatic mutation leads to high mutant frequency at hypoxanthine-guanine phosphoribosyltransferase gene

    Energy Technology Data Exchange (ETDEWEB)

    Jett, J. [Lawrence Livermore National Lab., CA (United States)

    1994-12-01

    While characterizing the background mutation spectrum of the Hypoxathine-guanine phosphoribosyltransferase (HPRT) gene in a healthy population, an outlier with a high mutant frequency of thioguanine resistant lymphocytes was found. When studied at the age of 46, this individual had been smoking 60 cigarettes per day for 38 years. His mutant frequency was calculated at 3.6 and 4.2x10{sup {minus}4} for two sampling periods eight months apart. Sequencing analysis of the HPRT gene in his mutant thioguanine resistant T lymphocytes was done to find whether the cells had a high rate of mutation, or if the mutation was due to a single occurrence of mutation and, if so, when in the T lymphocyte development the mutation occurred. By T-cell receptor analysis it has been found that out of 35 thioguanine resistant clones there was no dominant gamma T cell receptor gene rearrangement. During my appointment in the Science & Engineering Research Semester, I found that 34 of those clones have the same base substitution of G{yields}T at cDNA position 197. Due to the consistent mutant frequency from both sampling periods and the varying T cell receptors, the high mutant frequency cannot be due to recent proliferation of a mature mutant T lymphocyte. From the TCR and DNA sequence analysis we conclude that the G{yields}T mutation must have occurred in a T lymphocyte precursor before thymic differentiation so that the thioguanine resistant clones share the same base substitution but not the same gamma T cell receptor gene.

  20. NK cell activite in C157BL/Ka mice during the development of radiation induced thymic lymphomas

    International Nuclear Information System (INIS)

    Noel, A.; Schaaf-Lafontaine, N.; Defresne, M.P.; Boniver, J.

    1985-01-01

    Treatment of C57BL/Ka mice with a split dose whole-body irradiation (four weekly irradiations of 1,75 Gy) induces the development of thymic lymphomas. NK activity of spleen cells has been determined at several internals after leukemogenic treatment. Two days after irradiations, NK activity is normal and decreases strongly after one week. This period of decline persists during about one month. Then, NK activity restores and reaches control values. Lymphomas appear in spite of NK activity restauration. The diminution of NK activity during the preleukemic period could favour preleukemic cells apparition [fr

  1. Molecular characterization of non-thymic lymphomas in mice exposed to continuous low-dose-rate g-ray irradiation

    International Nuclear Information System (INIS)

    Takabatake, T.; Fujikawa, K.; Nakamura, S.; Tanaka, S.; Tanaka, I.; Tanaka-Braga III, I.; Sunaga, Y.; Ichinoche, K.; Sato, F.; Tanaka, K.; Matsumoto, T.

    2004-01-01

    To investigate the effects of continuous low-dose-rate irradiation on life span and neoplasm incidence, SPE B6C3 F1 mice were irradiated with 137Cs-ray at dose-rates of 20, 1 and 0.05 mGy/day with accumulated doses equivalent to 8000, 40 and 20 mGy, respectively. Examination of a total of 3,000 irradiated and 1,000 non-irradiated control mice showed that the life spans of the both sexes irradiated at 20 mGy/day, respectively. Examination of a total of 3,000 irradiated and 1,000 non-irradiated control mice showed that the life spans of the both sexes irradiated at 20 mGy/day were significantly shorter than that of the non-irradiated group. No significant difference in the cause of death and mortality rates was found between the groups. However, non-thymic lymphomas, the most common lethal neoplasm, showed a tendency to develop at an earlier age in mice irradiated with 20 mGy/day, regardless of sex. to obtain clues on the molecular mechanisms underlying the earlier development of non-thymic lymphomas in 20 mGy/day irradiated group, detailed molecular characterizations of non-thymic lymphomas with respect to B-cell or T-cell origin was done by detecting rearrangements in immunoglobulin heavy gene and in T-cell receptor b-and g chain genes by Southem hybridization method. to determine whether the early development of non-thymic lymphomas in 20 mGy/day irradiated group is associated wi the any recurrent chromosomal imbalance such as deletions and amplifications, the genome-wide scanning is also currently in progress by both LOH and array CGH methods. Present data obtained by LOH method show that deletions in parts of chromosomes 11 and 12 were more frequent than in chromosomes 2, 4 and 14 in both the non-irradiated control and 20 mGy/day irradiated groups. this work is supported by grants from Aomori Prefecture, Japan. (Author)

  2. {sup 18}F-FDG uptake on PET in primary mediastinal non-thymic neoplasm: A clinicopathological study

    Energy Technology Data Exchange (ETDEWEB)

    Kaira, Kyoichi, E-mail: kkaira1970@yahoo.co.jp [Division of Thoracic Oncology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Abe, Masato [Division of Pathology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Nakagawa, Kazuo; Ohde, Yasuhisa; Okumura, Takehiro [Division of Thoracic Surgery, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Takahashi, Toshiaki; Murakami, Haruyasu; Shukuya, Takehito; Kenmotsu, Hirotsugu; Naito, Tateaki [Division of Thoracic Oncology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Hayashi, Isamu [Division of Pathology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Oriuchi, Noboru [Department of Diagnostic Radiology and Nuclear medicine, Gunma University Graduate School of Medicine, Showa-machi, Maebashi 371-8511, Gunma (Japan); Endo, Masahiro [Division of Diagnostic Radiology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Kondo, Haruhiko [Division of Thoracic Surgery, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Nakajima, Takashi [Division of Pathology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan); Yamamoto, Nobuyuki [Division of Thoracic Oncology, Shizuoka Cancer Center, 1007 Shimonagakubo Nagaizumi-cho, Sunto-gun, Shizuoka 411-8777 (Japan)

    2012-09-15

    Background: The usefulness of 2-[{sup 18}F]-fluoro-2-deoxy-D-glucose ({sup 18}F-FDG) positron emission tomography (PET) has been investigated in thymic epithelial tumors. However, little is known about PET imaging of {sup 18}F-FDG in primary non-thymic mediastinal neoplasms. The aim of this study is to explore the clinicopathological significance of {sup 18}F-FDG PET in primary mediastinal (non-thymic) neoplasms. Methods: Twenty-one patients with mediastinal neoplasms who underwent {sup 18}F-FDG PET before treatment were included in this study. Tumor sections were stained by immunohistochemistry for glucose transporter 1 (Glut1); glucose transporter 3 (Glut3); hypoxia-inducible factor-1 alpha (HIF-1α); hexokinase I; vascular endothelial growth factor (VEGF); microvessels (CD34); epidermal growth factor receptor (EGFR); Akt/mTOR signaling pathway (p-Akt and p-mTOR); cell cycle control (p53). Results: Seventeen of 21 patients were imaged on PET system using {sup 18}F-FDG, but 4 patients with a histology of cyst showed nothing abnormal in PET scans. The histology of the resected tumors was as follows: 6 schwannoma, 3 teratoma, 4 cyst, 3 sarcoma, 1 undifferentiated carcinoma, 1 seminoma, 1 mediastinal goiter, 1 ganglioneuroma, and 1 Hodgkin lymphoma. {sup 18}F-FDG uptake was significantly correlated with Glut1, HIF-1α, EGFR, p-Akt and p-S6K. These biomarkers were highly expressed in schwannoma, teratoma and high grade malignancies, whereas all patients with cyst and ganglioneuroma had no positive expression of these biomarkers. High uptake of {sup 18}F-FDG was significant associated with Glut1, VEGF, EGFR, p-Akt, p-S6K and tumor maximal size. Conclusion: The amount of {sup 18}F-FDG uptake in primary mediastinal non-thymic neoplasms is determined by the presence of glucose metabolism (Glut1), hypoxia (HIF-1α) and upstream components of HIF-1α (EGFR, p-Akt and p-S6K)

  3. Thymic Nurse Cells Participate in Heterotypic Internalization and Repertoire Selection of Immature Thymocytes; Their Removal from the Thymus of Autoimmune Animals May be Important to Disease Etiology.

    Science.gov (United States)

    Guyden, J C; Martinez, M; Chilukuri, R V E; Reid, V; Kelly, F; Samms, M-O D

    2015-01-01

    Thymic nurse cells (TNCs) are specialized epithelial cells that reside in the thymic cortex. The initial report of their discovery in 1980 showed TNCs to contain up to 200 thymocytes within specialized vacuoles in their cytoplasm. Much has been reported since that time to determine the function of this heterotypic internalization event that exists between TNCs and developing thymocytes. In this review, we discuss the literature reported that describes the internalization event and the role TNCs play during T cell development in the thymus as well as why these multicellular complexes may be important in inhibiting the development of autoimmune diseases.

  4. Escape angles in bulk chi((2)) soliton interactions

    DEFF Research Database (Denmark)

    Johansen, Steffen Kjær; Bang, Ole; Sørensen, Mads Peter

    2002-01-01

    We develop a theory for nonplanar interaction between two identical type I spatial solitons propagating at opposite, but arbitrary transverse angles in quadratic nonlinear (or so-called chi((2))) bulk, media. We predict quantitatively the outwards escape angle, below which the solitons turn around...

  5. Leaflet escape in a new bileaflet mechanical valve: TRI technologies.

    Science.gov (United States)

    Bottio, Tomaso; Casarotto, Dino; Thiene, Gaetano; Caprili, Luca; Angelini, Annalisa; Gerosa, Gino

    2003-05-13

    Leaflet escape is a mode of structural valve failure for mechanical prostheses. This complication previously has been reported for both monoleaflet and bileaflet valve models. We report 2 leaflet escape occurrences observed in 2 patients who underwent valve replacement with a TRI Technologies valve prosthesis. At the University of Padua, between November 2000 and February 2002, 36 TRI Technologies valve prostheses (26 aortic and 10 mitral) were implanted in 34 patients (12 women and 22 men) with a mean age of 59.9+/-10.3 years (range, 30 to 75 years). There were 5 deaths: 3 in hospital, 1 early after discharge, and 1 late. Two patients experienced a catastrophic prosthetic leaflet escape; the first patient was a 52-year-old man who died 10 days after aortic valve and ascending aorta replacement, and the second was a 58-year-old man who underwent a successful emergency reoperation 20 months after mitral valve replacement. Examination of the explanted prostheses showed in both cases a leaflet escape caused by a leaflet's pivoting system fracture. Prophylactic replacement was then successfully accomplished so far in 12 patients, without evidence of structural valve failure in any of them. Among other significant postoperative complications, we observed 3 major thromboembolisms, 1 hemorrhage, and 1 paravalvular leak. These catastrophes prompted us to interrupt the implantation program, and they cast a shadow on the durability of the TRI Technologies valve prosthesis because of its high risk of structural failure.

  6. EscapeScape: Simulating Ecopedagogy for the Tourist

    Science.gov (United States)

    Nakagawa, Yoshifumi

    2018-01-01

    Environmental education as a theory and practice of ecopedagogical simulation positively acknowledges various accidental happenings in the learner's experience. By working with and on the accidents, the learner is encouraged to imagine the real object that escapes his/her experience and thus cannot be and should not be reduced into human…

  7. 46 CFR 169.313 - Means of escape.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Means of escape. 169.313 Section 169.313 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Construction... apart, uniform for the length of the ladder; (3) At least 3 inches from the nearest permanent object in...

  8. Entrapment and Escape: Inventional Metaphors in Ronald Reagan's Economic Rhetoric.

    Science.gov (United States)

    Aden, Roger C.

    1989-01-01

    Examines Ronald Reagan's use of inventional metaphors of entrapment and escape, language meshing with the American public's perception of the economy in the early 1980s. Notes that Reagan's reliance on inventional metaphors produced a rigidity in his approach to new situations, ultimately damaging his ability to lead the nation. (MM)

  9. Escape rate from strange sets as an eigenvalue

    International Nuclear Information System (INIS)

    Tel, T.

    1986-06-01

    A new method is applied for calculating the escape rate from chaotic repellers or semi-attractors, based on the eigenvalue problem of the master equation of discrete dynamical systems. The corresponding eigenfunction is found to be smooth along unstable directions and to be, in general, a fractal measure. Examples of one and two dimensional maps are investigated. (author)

  10. The escape of brownian particle over potential barriers

    International Nuclear Information System (INIS)

    Zhong Yunxiao

    1985-01-01

    A convenient method is introduced to calculate the rate of escape of Brownian particle over potential barriers by exact solution of Smoluchowskian equation. This method is applied to calculate the nuclear fission probabilities. The results for four different cases are compared with the results of other theories

  11. Escape manoeuvres in the spiny dogfish (Squalus acanthias).

    Science.gov (United States)

    Domenici, Paolo; Standen, Emily M; Levine, Robert P

    2004-06-01

    The locomotor performance of dogfish during escape responses was observed by means of high-speed video. Dogfish show C-type escape responses that are comparable with those shown previously in teleosts. Dogfish show high variability of turning rates of the anterior part of the body (head to centre of mass), i.e. with peak values from 434 to 1023 deg. s(-1). We suggest that this variability may be due to the presence of two types of escape manoeuvres, i.e. responses with high and low turning rates, as previously found in a teleost species. Fast responses (i.e. with high maximum turning rates, ranging between 766 and 1023 deg. s(-1)) showed significantly higher locomotor performance than slow responses (i.e. with low maximum turning rates, ranging between 434 and 593 deg. s(-1)) in terms of distance covered, speed and acceleration, although no differences were found in the turning radius of the centre of mass during the escape manoeuvres. The existence of two types of escape responses would have implications in terms of both neural control and muscular activation patterns. When compared with literature data for the locomotor performance of bony fishes, dogfish showed relatively low speed and acceleration, comparable turning rates and a turning radius that is in the low part of the range when compared with teleosts, indicating relatively high manoeuvrability. The locomotor performance observed in dogfish is consistent with their morphological characteristics: (1) low locomotor performance associated with low thrust developed by their relatively small posterior depth of section and (2) relatively high manoeuvrability associated with their high flexibility.

  12. Thymic size in uninfected infants born to HIV-positive mothers and fed with pasteurized human milk

    DEFF Research Database (Denmark)

    Jeppesen, Dorthe Lisbeth; Hasselbalch, H; Ersbøll, A K

    2003-01-01

    AIM: To examine the size of the thymus in uninfected infants born to HIV-positive mothers and to study the effects of feeding by human donor milk on the size of the thymus in these infants. METHODS: The absolute and relative thymic size was assessed by sonography as thymic index (Ti), and the Ti....../weight-ratio (Ti/w) at birth and at 4 mo of age in 12 healthy uninfected infants born to HlV-infected mothers. All infants were exclusively fed pasteurized donor milk. The results were compared with those obtained from a previous cohort of exclusively breastfed, partially breastfed and exclusively formula......-fed infants. RESULTS: At birth the Ti was reduced in infants born to HIV-infected mothers in comparison with that in control infants but this difference disappeared when their birthweights were taken into consideration (Ti/w-ratio). At 4 mo of age the geometric mean Ti of infants fed donor milk was 23...

  13. IL-4/IL-13 Signaling Inhibits the Potential of Early Thymic Progenitors To Commit to the T Cell Lineage.

    Science.gov (United States)

    Barik, Subhasis; Miller, Mindy M; Cattin-Roy, Alexis N; Ukah, Tobechukwu K; Chen, Weirong; Zaghouani, Habib

    2017-10-15

    Early thymic progenitors (ETPs) are endowed with diverse potencies and can give rise to myeloid and lymphoid lineage progenitors. How the thymic environment guides ETP commitment and maturation toward a specific lineage remains obscure. We have previously shown that ETPs expressing the heteroreceptor (HR) comprising IL-4Rα and IL-13Rα1 give rise to myeloid cells but not T cells. In this article, we show that signaling through the HR inhibits ETP maturation to the T cell lineage but enacts commitment toward the myeloid cells. Indeed, HR + ETPs, but not HR - ETPs, exhibit activated STAT6 transcription factor, which parallels with downregulation of Notch1, a critical factor for T cell development. Meanwhile, the myeloid-specific transcription factor C/EBPα, usually under the control of Notch1, is upregulated. Furthermore, in vivo inhibition of STAT6 phosphorylation restores Notch1 expression in HR + ETPs, which regain T lineage potential. In addition, upon stimulation with IL-4 or IL-13, HR - ETPs expressing virally transduced HR also exhibit STAT6 phosphorylation and downregulation of Notch1, leading to inhibition of lymphoid, but not myeloid, lineage potential. These observations indicate that environmental cytokines play a role in conditioning ETP lineage choice, which would impact T cell development. Copyright © 2017 by The American Association of Immunologists, Inc.

  14. A comparative study of PD-L1 immunohistochemical assays with four reliable antibodies in thymic carcinoma.

    Science.gov (United States)

    Sakane, Tadashi; Murase, Takayuki; Okuda, Katsuhiro; Takino, Hisashi; Masaki, Ayako; Oda, Risa; Watanabe, Takuya; Kawano, Osamu; Haneda, Hiroshi; Moriyama, Satoru; Saito, Yushi; Yamada, Takeshi; Nakanishi, Ryoichi; Inagaki, Hiroshi

    2018-01-23

    Currently, four immunohistochemical assays are registered with the US Food and Drug Administration to detect the expression of PD-L1. We investigated the PD-L1 expression in thymic carcinomas using these four diagnostic assays. The cases of 53 patients were reviewed and their specimens were subjected to four PD-L1 assays with different antibodies (SP142, SP263, 22C3, and 28-8). The PD-L1 expression in tumor cells (TCs) and immune cells (ICs) was evaluated. In TCs, the four assays showed similar scores in each case. Histopathologically, high TC scores were observed in squamous cell carcinomas (SqCCs). Meanwhile, there were no significant relationships among the IC scores in the four assays. In SqCCs, the high expression of PD-L1 (defined as ≥50% TC score) in TCs tended to be associated with early stage cancer. The patients with high expression levels of PD-L1 tended to show longer overall survival in the 22C3 assays (p=0.0200). In thymic carcinomas, the staining pattern showed high concordance among the four assays when TCs - rather than ICs - were stained. High PD-L1 positivity in TCs, especially in SqCCs, indicated that PD-1/PD-L1 targeted therapy may be a promising therapeutic approach.

  15. Thymic and lymph node mesenchymal subsets can be derived from PDGFRα/β+Gp38+CD34+ICAM1- vascular adventitial precursors

    DEFF Research Database (Denmark)

    Sitnik, Katarzyna Maria; Wendland, Kerstin; Weishaupt, Holger

    While discrete Gp38- and Gp38+ mesenchymal populations have previously been described in the lymph nodes (LNs) and in the thymus the putative relationship between LN and thymic mesenchymal cells remains unclear. Here, using transcriptome profiling as well as phenotypic and localization studies we...

  16. Cell-intrinsic role for NF-kappa B-inducing kinase in peripheral maintenance but not thymic development of Foxp3+ regulatory T cells in mice.

    Directory of Open Access Journals (Sweden)

    Susan E Murray

    Full Text Available NF-κB inducing kinase (NIK, MAP3K14 is a key signaling molecule in non-canonical NF-κB activation, and NIK deficient mice have been instrumental in deciphering the immunologic role of this pathway. Global ablation of NIK prevents lymph node development, impairs thymic stromal development, and drastically reduces B cells. Despite altered thymic selection, T cell numbers are near normal in NIK deficient mice. The exception is CD4(+ regulatory T cells (Tregs, which are reduced in the thymus and periphery. Defects in thymic stroma are known to contribute to impaired Treg generation, but whether NIK also plays a cell intrinsic role in Tregs is unknown. Here, we compared intact mice with single and mixed BM chimeric mice to assess the intrinsic role of NIK in Treg generation and maintenance. We found that while NIK expression in stromal cells suffices for normal thymic Treg development, NIK is required cell-intrinsically to maintain peripheral Tregs. In addition, we unexpectedly discovered a cell-intrinsic role for NIK in memory phenotype conventional T cells that is masked in intact mice, but revealed in BM chimeras. These results demonstrate a novel role for NIK in peripheral regulatory and memory phenotype T cell homeostasis.

  17. Activation of the aryl hydrocarbon receptor reduces the number of precursor and effector T cells, but preserves thymic CD4(+)CD25(+)Foxp3(+) regulatory T cells

    NARCIS (Netherlands)

    Schulz, V.J.; Smit, J.J.; Bol-Schoenmakers, M.; van Duursen, M.B.M.; van den Berg, M.; Pieters, R.H.H.

    2012-01-01

    Aryl hydrocarbon receptor (AhR) activation suppresses immune responses, including allergic sensitization, by increasing the percentage of regulatory (Treg) cells. Furthermore, AhR activation is known to affect thymic precursor T cells. However, the effect of AhR activation on intrathymic

  18. Sleep Deprivation, Allergy Symptoms, and Negatively Reinforced Problem Behavior.

    Science.gov (United States)

    Kennedy, Craig H.; Meyer, Kim A.

    1996-01-01

    A study of the relationship between presence or absence of sleep deprivation, allergy symptoms, and the rate and function of problem behavior in three adolescents with moderate to profound mental retardation found that problem behavior was negatively reinforced by escape from instruction, and both allergy symptoms and sleep deprivation influenced…

  19. CCR5 Targeted Cell Therapy for HIV and Prevention of Viral Escape

    Directory of Open Access Journals (Sweden)

    Gero Hütter

    2015-07-01

    Full Text Available Allogeneic transplantation with CCR5-delta 32 (CCR5-d32 homozygous stem cells in an HIV infected individual in 2008, led to a sustained virus control and probably eradication of HIV. Since then there has been a high degree of interest to translate this approach to a wider population. There are two cellular ways to do this. The first one is to use a CCR5 negative cell source e.g., hematopoietic stem cells (HSC to copy the initial finding. However, a recent case of a second allogeneic transplantation with CCR5-d32 homozygous stem cells suffered from viral escape of CXCR4 quasi-species. The second way is to knock down CCR5 expression by gene therapy. Currently, there are five promising techniques, three of which are presently being tested clinically. These techniques include zinc finger nucleases (ZFN, clustered regularly interspaced palindromic repeats/CRISPR-associated protein 9 nuclease (CRISPR/Cas9, transcription activator-like effectors nuclease (TALEN, short hairpin RNA (shRNA, and a ribozyme. While there are multiple gene therapy strategies being tested, in this review we reflect on our current knowledge of inhibition of CCR5 specifically and whether this approach allows for consequent viral escape.

  20. A Prospective Phase II Study of Cisplatin and Cremophor EL-Free Paclitaxel (Genexol-PM) in Patients with Unresectable Thymic Epithelial Tumors.

    Science.gov (United States)

    Kim, Hae Su; Lee, Ji Yun; Lim, Sung Hee; Sun, Jong-Mu; Lee, Se Hoon; Ahn, Jin Seok; Park, Keunchil; Moon, Seung Hwan; Ahn, Myung-Ju

    2015-12-01

    We conducted a prospective phase II study of cisplatin plus cremophor EL-free paclitaxel (Genexol-PM) in patients with unresectable thymic epithelial tumors to determine the efficacy and tolerability of the combination therapy. Patients were treated with cisplatin (70 mg/m) and Genexol-PM (230 mg/m) on day 1 of a 3-week cycle as first-line palliative chemotherapy. The primary end point of this study was objective response rate, and the secondary end points included toxicity, progression-free survival (PFS), overall survival, correlation between early 18F-fluorodeoxyglucose positron emission tomography/computed tomography response and PFS, and correlation between baseline flurododeoxyglucose uptake and histology. Forty-two patients with unresectable thymoma (n = 14) or thymic carcinoma (n = 28) were enrolled between May 2012 and October 2014. The median age was 59 years (range: 25-77) and 30 patients (71%) were male, and 39 patients (93%) had an ECOG PS of 1. The median number of treatment cycles was six (range: 1-6). For 40 assessable patients, the objective response rate was 62.5% (95% confidence interval [CI]: 47.6-77.4) with rates of 46% (95% CI: 23.3-76.9) for advanced thymoma (n = 13) and 70% (95% CI: 52.0-82.1) for thymic carcinoma (n = 27). With a median follow-up of 15.5 months, the median PFS for all 42 patients was 9.8 months (11.4 months for thymoma versus 8.1 months for thymic carcinoma). The 2-year overall survival was 77.9% for thymoma and 65.9% for thymic carcinoma. There were no treatment-related deaths. The most common grade 3 and 4 treatment-related adverse event was neutropenia in 11 patients (26%). Eight patients (19%) experienced grade 2 hypersensitivity reactions. There was no correlation between early positron emission tomography response and PFS, but tumor histology (thymoma versus thymic carcinoma) was correlated with SUVmax before chemotherapy. These data suggest that combination of cisplatin and Genexol-PM is highly effective and

  1. Elimination of self-reactive T cells in the thymus: a timeline for negative selection.

    Directory of Open Access Journals (Sweden)

    Ivan Lilyanov Dzhagalov

    Full Text Available The elimination of autoreactive T cells occurs via thymocyte apoptosis and removal by thymic phagocytes, but the sequence of events in vivo, and the relationship between thymocyte death and phagocytic clearance, are unknown. Here we address these questions by following a synchronized cohort of thymocytes undergoing negative selection within a three-dimensional thymic tissue environment, from the initial encounter with a negative selecting ligand to thymocyte death and clearance. Encounter with cognate peptide-MHC complexes results in rapid calcium flux and migratory arrest in auto-reactive thymocytes over a broad range of peptide concentrations, followed by a lag period in which gene expression changes occurred, but there was little sign of thymocyte death. Caspase 3 activation and thymocyte loss were first detectable at 2 and 3 hours, respectively, and entry of individual thymocytes into the death program occurred asynchronously over the next 10 hours. Two-photon time-lapse imaging revealed that thymocyte death and phagocytosis occurred simultaneously, often with thymocytes engulfed prior to changes in chromatin and membrane permeability. Our data provide a timeline for negative selection and reveal close coupling between cell death and clearance in the thymus.

  2. Library Lockdown: An escape room by kids for the community

    Directory of Open Access Journals (Sweden)

    Jennifer Thoegersen

    2016-11-01

    Full Text Available In Brief Hoping to bring the unexpected to Nebraska City, the Morton-James Public Library applied for an ALA Association for Library Service to Children Curiosity Creates grant to undertake an ambitious project: build an escape room. In a library storage room. With children. The hope was  by trying something completely different, we could increase interest in the library throughout the community and build a sense of ownership in the participants, while encouraging creativity and having a lot of fun. Library Lockdown was a four-month program that brought several dozen kids together—age 8 to 13—to build a fully-functioning escape room. Their creation, the Lab of Dr. Morton McBrains, is now open for business.

  3. Calculations of condensed moisture escape from a NPP spray pond

    International Nuclear Information System (INIS)

    Bratuta, Eh. G.; Yaroshenko, T.I.

    1988-01-01

    A method for calculating water losses due to condensed moisture escape with a wind away from a spray pond used for cooling steam turbine condensator water and emergency nuclear reactor cooling is developed. The method is based on solving a three-dimensional equation of single drop motion, assuming that during the whole flight only gravity and aerodynamic resistance forces act on a drop. The basic parameter variation ranges are the following: 0-18 m/s wind velocity, 0.04-0.12 MPa pressure drop at the nozzle output, 1-2 m height of sprayers above the pond mirror. The given method permits to determine both the amount of circulation water loss and the local liquid flow rate distribution pattern as well as the area around the pond receiving the escaped moisture that is necessary for estimating the ecological situation near a NPP

  4. Fixation and escape times in stochastic game learning

    International Nuclear Information System (INIS)

    Realpe-Gomez, John; Szczesny, Bartosz; Galla, Tobias; Dall’Asta, Luca

    2012-01-01

    Evolutionary dynamics in finite populations is known to fixate eventually in the absence of mutation. We here show that a similar phenomenon can be found in stochastic game dynamical batch learning, and investigate fixation in learning processes in a simple 2×2 game, for two-player games with cyclic interaction, and in the context of the best-shot network game. The analogues of finite populations in evolution are here finite batches of observations between strategy updates. We study when and how such fixation can occur, and present results on the average time-to-fixation from numerical simulations. Simple cases are also amenable to analytical approaches and we provide estimates of the behaviour of so-called escape times as a function of the batch size. The differences and similarities with escape and fixation in evolutionary dynamics are discussed. (paper)

  5. Quantum and thermal phase escape in extended Josephson systems

    International Nuclear Information System (INIS)

    Kemp, A.

    2006-01-01

    In this work I examine phase escape in long annular Josephson tunnel junctions. The sine-Gordon equation governs the dynamics of the phase variable along the junction. This equation supports topological soliton solutions, which correspond to quanta of magnetic flux trapped in the junction barrier. For such Josephson vortices an effective potential is formed by an external magnetic field, while a bias current acts as a driving force. Both together form a metastable potential well, which the vortex is trapped in. When the driving force exceeds the pinning force of the potential, the vortex escapes and the junction switches to the voltage state. At a finite temperature the driving force fluctuates. If the junction's energy scale is small, the phase variable can undergo a macroscopic quantum tunneling (MQT) process at temperatures below the crossover temperature. Without a vortex trapped, the metastable state is not a potential minimum in space, but a potential minimum at zero phase difference. (orig.)

  6. Partial control of chaotic transients using escape times

    International Nuclear Information System (INIS)

    Sabuco, Juan; Zambrano, Samuel; Sanjuan, Miguel A F

    2010-01-01

    The partial control technique allows one to keep the trajectories of a dynamical system inside a region where there is a chaotic saddle and from which nearly all the trajectories diverge. Its main advantage is that this goal is achieved even if the corrections applied to the trajectories are smaller than the action of environmental noise on the dynamics, a counterintuitive result that is obtained by using certain safe sets. Using the Henon map as a paradigm, we show here the deep relationship between the safe sets and the sets of points with different escape times, the escape time sets. Furthermore, we show that it is possible to find certain extended safe sets that can be used instead of the safe sets in the partial control technique. Numerical simulations confirm our findings and show that in some situations, the use of extended safe sets can be more advantageous.

  7. The production and escape of nitrogen atoms on Mars

    Science.gov (United States)

    Fox, J. L.

    1993-01-01

    Updated rate coefficients and a revised ionosphere-thermosphere model are used to compute the production rates and densities of odd nitrogen species in the Martian atmosphere. Computed density profiles for N(4S), N(2D), N(2P), and NO are presented. The model NO densities are found to be about a factor of 2-3 less than those measured by the Viking 1 mass spectrometer. Revised values for the escape rates of N atoms from dissociative recombination and ionospheric reactions are also computed. Dissociative recombination is found to be comparable in importance to photodissociation at low solar activity, but it is still the most important escape mechanism for N-14 at high solar activity.

  8. Quantum and thermal phase escape in extended Josephson systems

    Energy Technology Data Exchange (ETDEWEB)

    Kemp, A.

    2006-07-12

    In this work I examine phase escape in long annular Josephson tunnel junctions. The sine-Gordon equation governs the dynamics of the phase variable along the junction. This equation supports topological soliton solutions, which correspond to quanta of magnetic flux trapped in the junction barrier. For such Josephson vortices an effective potential is formed by an external magnetic field, while a bias current acts as a driving force. Both together form a metastable potential well, which the vortex is trapped in. When the driving force exceeds the pinning force of the potential, the vortex escapes and the junction switches to the voltage state. At a finite temperature the driving force fluctuates. If the junction's energy scale is small, the phase variable can undergo a macroscopic quantum tunneling (MQT) process at temperatures below the crossover temperature. Without a vortex trapped, the metastable state is not a potential minimum in space, but a potential minimum at zero phase difference. (orig.)

  9. Heat shock protein 90-sheltered overexpression of insulin-like growth factor 1 receptor contributes to malignancy of thymic epithelial tumors.

    Science.gov (United States)

    Breinig, Marco; Mayer, Philipp; Harjung, Andreas; Goeppert, Benjamin; Malz, Mona; Penzel, Roland; Neumann, Olaf; Hartmann, Arndt; Dienemann, Hendrik; Giaccone, Giuseppe; Schirmacher, Peter; Kern, Michael André; Chiosis, Gabriela; Rieker, Ralf Joachim

    2011-04-15

    The underlying molecular mechanisms of thymic epithelial malignancies (TEMs) are poorly understood. Consequently, there is a lack of efficacious targeted therapies and patient prognosis remains dismal, particularly for advanced TEMs. We sought to investigate protumorigenic mechanism relevant to this understudied cancer. Recently established cell lines derived from thymic epithelial tumors were used as a model system. The antitumor activity of specific heat shock protein 90 (Hsp90) inhibitors was investigated by an analysis of cell viability, cell cycle, and apoptosis using MTT-assays and flow cytometry. Western blotting was used to investigate the altered expression of Hsp90 clients. Pharmacological inhibitors against select Hsp90 clients, as well as RNAi, were employed to test the relevance of each client independently. Tissue microarray analysis was performed to match the in vitro findings with observations obtained from patient-derived samples. Hsp90 inhibition significantly reduces cell viability of thymic carcinoma cells, induces cell cycle arrest and apoptosis, and blocks invasiveness. Hsp90 inhibition triggers the degradation of multiple oncogenic clients, for example insulin-like growth factor 1 receptor (IGF-1R), CDK4, and the inactivation of PI3K/Akt and RAF/Erk signaling. Mechanistically, the IGF/IGF-1R-signaling axis contributes to the establishment of the antiapoptotic phenotype of thymic cancer cells. Finally, IGF-1R is overexpressed in advanced TEMs. We have unraveled a novel protumorigenic mechanism in TEMs, namely Hsp90-capacitated overexpression of IGF-1R, which confers apoptosis evasion in malignant thymic epithelial cells. Our data indicate that Hsp90 inhibition, which simultaneously blocks multiple cancer hallmarks, represents a therapeutic strategy in TEMs that may merit evaluation in clinical trials. ©2011 AACR.

  10. UNESCO to blame:Reality or easy escape?

    OpenAIRE

    Pereira Roders, A Ana; Grigolon, AB Anna

    2015-01-01

    “UNESCO to blame” is a trend often observed in scholarly works. In those studies UNESCO is accused to privilege Eurocentric standards on heritage conservation. Is this reality or an easy escape? Can this trend be noted in other UNESCO reference texts? This article seeks to answer this question by studying the two main inscription-based conventions and their contribution to heritage management, while performing a data analysis on the countries behind these conventions, and their roles over tim...

  11. The escape of natural satellites from Mercury and Venus

    International Nuclear Information System (INIS)

    Kumar, S.S.

    1977-01-01

    It is suggested that the slow rotations of Mercury and Venus may be connected with the absence of natural satellites around them. If Mercury or Venus possessed a satellite at the time of formation, the tidal evolution would have caused the satellite to recede. At a sufficiently large distance from the planet, the Sun's gravitational influence makes the satellite orbit unstable. The natural satellites of Mercury and Venus might have escaped as a consequence of this instability. (Auth.)

  12. Escape of natural satellites from Mercury and Venus

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S S [Virginia Univ., Charlottesville (USA)

    1977-09-01

    It is suggested that the slow rotations of Mercury and Venus may be connected with the absence of natural satellites around them. If Mercury or Venus possessed a satellite at the time of formation, the tidal evolution would have caused the satellite to recede. At a sufficiently large distance from the planet, the Sun's gravitational influence makes the satellite orbit unstable. The natural satellites of Mercury and Venus might have escaped as a consequence of this instability.

  13. ESCAPE: an integrated climate model for the EC

    International Nuclear Information System (INIS)

    Rotmans, J.

    1992-01-01

    A framework has been developed for the evaluation of policy options for climate change, called ESCAPE (Evaluation of Strategies to address Climate change by Adapting to and Preventing Emissions). ESCAPE consists of a suite of linked models which enables scenarios of greenhouse gas emissions to be constructed and their impact on global and regional climate and sea level and sectors of the European economy to be assessed. Conclusions resulting from simulations with the ESCAPE 1.1 model include: the major problem of a climate change for the EC is a sea level rise; Greece, Italy, Portugal and Spain will be faced with higher costs in the agricultural sector; worldwide implementation of an EC carbon tax leads to about 12% lower worldwide CO 2 emissions; to stabilize CO 2 emissions an Ecotax of 18 dollars per barrel would be required; and in all cases the rate of global temperature increase will be above the rate of 0.1 degree C per decade for the coming 40 years. 2 figs

  14. Transitions between three swimming gaits in Paramecium escape.

    Science.gov (United States)

    Hamel, Amandine; Fisch, Cathy; Combettes, Laurent; Dupuis-Williams, Pascale; Baroud, Charles N

    2011-05-03

    Paramecium and other protists are able to swim at velocities reaching several times their body size per second by beating their cilia in an organized fashion. The cilia beat in an asymmetric stroke, which breaks the time reversal symmetry of small scale flows. Here we show that Paramecium uses three different swimming gaits to escape from an aggression, applied in the form of a focused laser heating. For a weak aggression, normal swimming is sufficient and produces a steady swimming velocity. As the heating amplitude is increased, a higher acceleration and faster swimming are achieved through synchronized beating of the cilia, which begin by producing oscillating swimming velocities and later give way to the usual gait. Finally, escape from a life-threatening aggression is achieved by a "jumping" gait, which does not rely on the cilia but is achieved through the explosive release of a group of trichocysts in the direction of the hot spot. Measurements through high-speed video explain the role of trichocysts in defending against aggressions while showing unexpected transitions in the swimming of microorganisms. These measurements also demonstrate that Paramecium optimizes its escape pattern by taking advantage of its inertia.

  15. Effective climate-energy solutions, escape routes and peak oil

    International Nuclear Information System (INIS)

    Bergh, Jeroen C.J.M. van den

    2012-01-01

    Many well-intended climate-energy strategies are ineffective in the absence of serious environmental regulation. This holds, among others, for direct support of clean energy, voluntary energy conservation, technical standards on a limited set of products, unilateral stringent carbon pricing, and awaiting peak oil as a climate strategy. All of these suffer from “escape routes” that indirectly increase CO 2 emissions and thus make the original strategy ineffective. On the other hand, environmental regulation alone may lead to a myopia-bias, stimulating early dominance of cost-effective technologies and a focus on incremental innovations associated with such technologies rather than on radical innovations. Although adopting a partial viewpoint keeps the analysis simple, we urgently need a more inclusive systems perspective on climate solutions. This will allow the formulation of an effective climate policy package that addresses the various escape routes. - Highlights: ► Many well-intended climate-energy strategies are ineffective because of escape routes. ► In this context the relationship between peak oil and climate policy receives attention. ► Environmental regulation alone creates myopia-bias, the resolution of which requires technology-specific policies. ► To formulate an effective climate policy package an inclusive systems perspective is needed.

  16. Escape Geography--Developing Middle-School Students' Sense of Place.

    Science.gov (United States)

    Allen, Rodney F.; Molina, Laurie E. S.

    1992-01-01

    Suggests a social studies unit on escaping geography. Examines escape from dangerous places including an airliner, hotel fire, or war zone or from a social situation such as a boring speech or party. Describes historic escapes such as the Underground Railroad and the Berlin Wall. Lists learning strategies such as awareness of space and cognitive…

  17. Thymic function and T cell parameters in a natural human experimental model of seasonal infectious diseases and nutritional burden

    Directory of Open Access Journals (Sweden)

    Morgan Gareth

    2011-06-01

    Full Text Available Abstract Background The study exploits a natural human experimental model of subsistence farmers experiencing chronic and seasonally modified food shortages and infectious burden. Two seasons existed, one of increased deprivation and infections (Jul-Dec, another of abundance and low infections (Jan-Jun; referred to as the hungry/high infection and harvest/low infection seasons respectively. Prior analysis showed a 10-fold excess in infectious disease associated mortality in young adults born in the hungry/high infection versus harvest/low infection season, and reduced thymic output and T cell counts in infancy. Here we report findings on the role of early life stressors as contributors to the onset of T cell immunological defects in later life. Methods We hypothesised that season of birth effects on thymic function and T cell immunity would be detectable in young adults since Kaplan-Meier survival curves indicated this to be the time of greatest mortality divergence. T cell subset analyses by flow-cytometry, sjTRECs, TCRVβ repertoire and telomere length by PCR, were performed on samples from 60 males (18-23 y selected to represent births in the hungry/high infection and harvest/low infection Results Total lymphocyte counts were normal and did not differ by birth season. CD3+ and CD4+ but not CD8+ counts were lower for those born during the hungry/high infection season. CD8+ telomere length also tended to be shorter. Overall, CD8+ TCRVβ repertoire skewing was observed with 'public' expressions and deletions seen in TCRVβ12/22 and TCRVβ24, respectively but no apparent effect of birth season. Conclusions We conclude that, although thymic function was unchanged, the CD4+ and CD3+ counts, and CD8+ telomere length results suggested that aspects of adult T cell immunity were under the influence of early life stressors. The endemicity of CMV and HBV suggested that chronic infections may modulate immunity through T cell repertoire development. The

  18. Hydroxyhydroquinone, a by-product of coffee bean roasting, increases intracellular Ca2+ concentration in rat thymic lymphocytes.

    Science.gov (United States)

    Kamae, Risa; Nojima, Shoko; Akiyoshi, Kenji; Setsu, Shoki; Honda, Sari; Masuda, Toshiya; Oyama, Yasuo

    2017-04-01

    Hydroxyhydroquinone (HHQ) is generated during coffee bean roasting. A cup of coffee contains 0.1-1.7 mg of HHQ. The actions of HHQ on mammalian DNA were examined because HHQ is a metabolite of benzene, which causes leukemia. Currently, information on the cellular actions of HHQ is limited. We examined the effects of sublethal levels of HHQ on the concentration of intracellular Ca 2+ in rat thymic lymphocytes by using a flow cytometric technique with fluorescent probes. HHQ at 10 μM or more significantly elevated intracellular Ca 2+ levels by increasing the membrane permeability of divalent cations, resulting in hyperpolarization via the activation of Ca 2+ -dependent K + channels. HHQ-induced changes in the intracellular Ca 2+ concentration and membrane potential may affect the cell functions of lymphocytes. HHQ-reduced coffee may be preferable in order to avoid the possible adverse effects of HHQ. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Apparent failure of thymic epithelium transplants to alter the course of autoimmune disease in NZB/W mice

    International Nuclear Information System (INIS)

    Morrow, W.J.W.; Nayak, R.C.; Cooke, A.; Roitt, I.M.

    1982-01-01

    Thymic epithelium from neonatal DBA/2 mice (H-2sup(d)) was placed under the kidney capsule of 10- to 12-wk-old female NZB/W mice (H-2sup(d/z)). Donor epithelium, equivalent to 1-2 lobes of neonatal thymus, was either irradiated (1300 rad.) or cultured for 7 days in order to minimise host-versus-graft reactions. Histological examination showed that the epithelium repopulated and remained in place until the end of the experiment, with no sign of rejection. Despite this, the treated animals lived no longer than the untreated or sham operated controls. Levels of anti-nuclear antibody and serum IgM (normally highly elevated in these animals) were not significantly different in any group. (Auth.)

  20. The effect of embryonal thymic calf extracts on neonatally thymectomized mice and on mice lethally irradiated with gamma rays

    International Nuclear Information System (INIS)

    Czaplicki, J.; Blonska, B.; Stec, L.

    1981-01-01

    The effect of embryonal thymic calf extracts (ETCE) on mice thymectomized at birth was investigated. ETCE was found to induce an increase in leukopenia and decrease in the level of serum gamma globulins; it also reduced survival time in mice. The effect of ETCE on lethally irradiated mice was also examined. Only long-term administration of ETCE prior to gamma irradiation at 750 rad prolonged the survival time of mice (40% permanent survival) as compared with irradiated controls; the leukocytes from mice retained mitotic capability. Neither long-term treatment with ETCE prior to irradiation at 1000 rad, nor short-term administration prior to 750 rad affected survival time. ETCE administered after irradiation of mice with 750 rad caused a rapid decrease in blood leukocytes and a significantly lowered survival time. (Auth.)

  1. Thymic size in uninfected infants born to HIV-positive mothers and fed with pasteurized human milk

    DEFF Research Database (Denmark)

    Jeppesen, Dorthe Lisbeth; Hasselbalch, H; Ersbøll, A K

    2003-01-01

    /weight-ratio (Ti/w) at birth and at 4 mo of age in 12 healthy uninfected infants born to HlV-infected mothers. All infants were exclusively fed pasteurized donor milk. The results were compared with those obtained from a previous cohort of exclusively breastfed, partially breastfed and exclusively formula.......8 and the mean Ti/w-ratio was 4.2. Compared with those of exclusively breastfed infants, the Ti and Ti/w-ratio of infants fed donor milk were significantly reduced (p infants compared with that in the formula-fed infants (p = 0.02). CONCLUSION: At birth...... with thymic size in infants that were exclusively formula fed....

  2. The petit rat (pet/pet), a new semilethal mutant dwarf rat with thymic and testicular anomalies.

    Science.gov (United States)

    Chiba, Junko; Suzuki, Katsushi; Suzuki, Hiroetsu

    2008-12-01

    The petit rat (pet/pet) is a recently discovered semilethal mutant dwarf. The neonatal pet/pet rats had a low body weight and small thymus and testis. During the first 3 d after birth, 50% of the male and 80% of the female pet/pet pups were lost or found dead. Surviving pet/pet rats showed marked retardation of postnatal growth, and their body weights were 41% (female rats) and 32% (male rats) of those of normal rats at the adult stage. The pet/pet rats exhibited proportional dwarfism, and their longitudinal bones were shorter than those of controls without skeletal malformations. Most organs of male pet/pet rats, especially the thymus, testis, adipose tissue surrounding the kidney, and accessory sex organs, weighed markedly less at 140 d of age than did those of their normal counterparts. The thymus of pet/pet rats was small with abnormal thymic follicles. Testes from pet/pet rats exhibited 2 patterns of abnormal histology. Spermatogenesis was present in testes that were only slightly anomalous, but the seminiferous tubules were reduced in diameter. In severely affected testes, most of the seminiferous tubules showed degeneration, and interstitial tissue was increased. Plasma growth hormone concentrations did not differ between pet/pet and normal male rats. The dwarf phenotype of pet/pet rats was inherited as an autosomal recessive trait. These results indicate that the pet/pet rat has a semilethal growth-hormone-independent dwarf phenotype that is accompanied by thymic and testicular anomalies and low birth weight.

  3. Differential regulation of caspase-9 by ionizing radiation- and UV-induced apoptotic pathways in thymic cells

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Mayumi; Koga, Satomi [Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Hiroshima 727-0023 (Japan); Tatsuka, Masaaki, E-mail: tatsuka@pu-hiroshima.ac.jp [Department of Life Sciences, Faculty of Life and Environmental Sciences, Prefectural University of Hiroshima, Hiroshima 727-0023 (Japan)

    2010-06-01

    In mouse thymic lymphoma 3SB cells bearing wild type p53, ionizing radiation (IR) and UV light are potent triggers of caspase-3-dependent apoptosis. Although cytochrome c was released from mitochondria as expected, caspase-9 activation was not observed in UV-exposed cells. Laser scanning confocal microscopy analysis showed that caspase-9 is localized in an unusual punctuated pattern in UV-induced apoptotic cells. In agreement with differences in the status of caspase-9 activation between IR and UV, subcellular protein fractionation experiments showed that pro-apoptotic apoptosis protease-activating factor 1 (Apaf-1), normally a part of the apoptosome assembled in response to the release of cytochrome c from mitochondria, and B-cell lymphoma extra long (Bcl-xL), an inhibitor of the change in mitochondrial membrane permeability, were redistributed by the IR-exposure but not by the UV-exposure. Instead of the sequestration of the capase-9/apoptosome activation in UV-induced apoptotic cells, the extrinsic apoptotic signaling generated by caspase-8 activation and consequent activation of B-cell lymphoma extra long (Bid) to release cytochrome c from mitochondria was observed. Thus, the post-mitochondrial apoptotic pathway downstream of cytochrome c release cannot operate the apoptosome function in UV-induced apoptosis in thymic 3SB cells. The intracellular redistribution and sequestration of apoptosis-related proteins upon mitochondrion-based apoptotic signaling was identified as a novel cellular mechanism to respond to DNA damage in an agent type-specific manner. This finding suggests that the kind of the critical ultimate apoptosis-inducing DNA lesion complex form resulting from the agent-specific DNA damage responses is important to determine which of apoptosis signals would be activated.

  4. T-cell receptor excision circles (TREC) in CD4+ and CD8+ T-cell subpopulations in atopic dermatitis and psoriasis show major differences in the emission of recent thymic emigrants

    DEFF Research Database (Denmark)

    Just, Helle L; Deleuran, Mette; Vestergaard, Christian

    2008-01-01

    . In contrast, both men and women with psoriasis had significantly reduced TREC levels, which were, on average, only 30% of that of healthy persons. In atopic dermatitis the levels of TREC declined with increasing levels of IgE, disease intensity and extent of eczema. Furthermore, patients with atopic......-cells, this indicates that atopic dermatitis patients can have compensatory emissions of thymic emigrants, whereas psoriatic patients do not, thus supporting different thymic function in these two diseases....

  5. Escape behaviour of birds in urban parks and cemeteries across Europe: Evidence of behavioural adaptation to human activity.

    Science.gov (United States)

    Morelli, Federico; Mikula, Peter; Benedetti, Yanina; Bussière, Raphaël; Jerzak, Leszek; Tryjanowski, Piotr

    2018-08-01

    Urban environments are very heterogeneous, and birds living in the proximity of humans have to adapt to local conditions, e.g. by changing their behavioural response to potential predators. In this study, we tested whether the escape distance of birds (measured as flight initiation distance; FID) differed between parks and cemeteries, areas characterized by different microhabitat conditions and human conduct, that are determinants of animal behaviour at large spatial scales. While escape behaviour of park populations of birds was often examined, cemetery populations have not been studied to the same extent and a large-scale comparison is still missing. Overall, we collected 2139 FID estimates for 44 bird species recorded in 79 parks and 90 cemeteries in four European countries: Czech Republic, France, Italy and Poland. Mixed model procedure was applied to study escape behaviour in relation to type of area (park or cemetery), environmental characteristics (area size, coverage by trees, shrubs, grass, chapels, tombstones, flowerbeds, number of street lamps) and human activity (human density, pedestrians speed and ratio of men/women). Birds allowed people closer in cemeteries than in parks in all countries. This pattern was persistent even when focusing on intraspecific differences in FID between populations of the most common bird species. Escape distance of birds was negatively correlated with the size of parks/cemeteries, while positively associated with tombstone coverage and human density in both types of habitat. Our findings highlight the ability of birds to adapt their behaviour to different types of urban areas, based on local environmental conditions, including the character of human-bird interactions. Our results also suggest that this behavioural pattern may be widespread across urban landscapes. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Escaping the Self: Identity, Group Identification and Violence

    Directory of Open Access Journals (Sweden)

    James Hardie-Bick

    2016-12-01

    Full Text Available This article draws on the early work of Erich Fromm. In Escape from Freedom Fromm (1969 [1941] directly addressed the psychological mechanisms of escape modern individuals employ to protect themselves from feelings of ontological insecurity and existential estrangement. The article builds on Fromm’s analysis by discussing the significance of his escape mechanisms for understanding the dynamic psychological attractions of identifying with entitative groups. Fromm’s work will be discussed in relation to Hogg’s recent work on uncertainty-identity theory. The aim of the article is to examine the advantages of combining Fromm’s psychoanalytic analysis with Hogg’s uncertainty-identity theory and to highlight the potential this approach has for understanding why groups engage in violent and destructive behaviour. Este artículo se inspira en las primeras obras de Erich Fromm. En El miedo a la libertad, Fromm (1969 [1941] abordó directamente los mecanismos psicológicos de evasión que los individuos modernos emplean para protegerse de los sentimientos de inseguridad ontológica y distanciamiento existencial. Este artículo se basa en el análisis de Fromm exponiendo el significado de sus mecanismos de evasión para entender las atracciones psicológicas dinámicas de identificación con grupos entitativos. Se analizará la obra de Fromm en relación con la obra reciente de Hogg sobre la teoría de incertidumbre identitaria. El objetivo del artículo es examinar las ventajas de combinar el análisis psicoanalítico de Fromm con la teoría de incertidumbre identitaria de Hogg, y destacar el potencial que tiene esta aproximación para comprender por qué los grupos adoptan un comportamiento violento y destructivo. DOWNLOAD THIS PAPER FROM SSRN: https://ssrn.com/abstract=2875737

  7. Escape trajectories of solar sails and general relativity

    Energy Technology Data Exchange (ETDEWEB)

    Kezerashvili, Roman Ya. [Physics Department, New York City College of Technology, City University of New York, 300 Jay Street, Brooklyn, NY 11201 (United States); Graduate School and University Center, City University of New York, 365 Fifth Avenue, New York, NY 10016 (United States); Vazquez-Poritz, Justin F., E-mail: jvazquez-poritz@citytech.cuny.ed [Physics Department, New York City College of Technology, City University of New York, 300 Jay Street, Brooklyn, NY 11201 (United States); Graduate School and University Center, City University of New York, 365 Fifth Avenue, New York, NY 10016 (United States)

    2009-11-16

    General relativity can have a significant impact on the long-range escape trajectories of solar sails deployed near the sun. For example, spacetime curvature in the vicinity of the sun can cause a solar sail traveling from about 4 solar radii to 2550 AU to be deflected by on the order of a million kilometers, and should therefore be taken into account at the beginning of the mission. There are a number of smaller general relativistic effects, such as frame dragging due to the slow rotation of the sun which can cause a deflection of more than one thousand kilometers.

  8. Diffusion escape through a cluster of small absorbing windows

    Energy Technology Data Exchange (ETDEWEB)

    Holcman, D [Department of Mathematics, Weizmann Institute of Science, Rehovot 76100 (Israel); Schuss, Z [Department of Mathematics, Tel-Aviv University, Tel-Aviv 69978 (Israel)

    2008-04-18

    We study the first eigenvalue of the Laplace equation in a bounded domain in R{sup d} (d=2,3) with mixed Neumann-Dirichlet (Zaremba) boundary conditions. The Neumann condition is imposed on most of the boundary and the Dirichlet boundary consists of a cluster of small windows. When the windows are well separated the first eigenvalue is asymptotically the sum of eigenvalues of mixed problems with a single Dirichlet window. However, when two or more Dirichlet windows cluster tightly together they interact nonlinearly. We compare our asymptotic approximation of the eigenvalue to the escape rate of simulated Brownian particles through the small windows.

  9. Chases and escapes the mathematics of pursuit and evasion

    CERN Document Server

    Nahin, Paul J

    2012-01-01

    We all played tag when we were kids. What most of us don't realize is that this simple chase game is in fact an application of pursuit theory, and that the same principles of games like tag, dodgeball, and hide-and-seek are also at play in military strategy, high-seas chases by the Coast Guard, and even romantic pursuits. In Chases and Escapes, Paul Nahin gives us the first complete history of this fascinating area of mathematics, from its classical analytical beginnings to the present day. Drawing on game theory, geometry, linear algebra, target-tracking algorithms, and much

  10. Experimental study of subsonic microjet escaping from a rectangular nozzle

    Science.gov (United States)

    Aniskin, V. M.; Maslov, A. A.; Mukhin, K. A.

    2016-10-01

    The first experiments on the subsonic laminar microjets escaping from the nozzles of rectangular shape are carried out. The nozzle size is 83.3x3823 microns. Reynolds number calculated by the nozzle height and the average flow velocity at the nozzle exit ranged from 58 to 154. The working gas was air at room temperature. The velocity decay and velocity fluctuations along the center line of the jet are determined. The fundamental difference between the laminar microjets characteristics and subsonic turbulent jets of macro size is shown. Based on measurements of velocity fluctuations it is shown the presence of laminar-turbulent transition in microjets and its location is determined.

  11. The age structure of selected countries in the ESCAP region.

    Science.gov (United States)

    Hong, S

    1982-01-01

    The study objective was to examine the age structure of selected countries in the Economic and Social Commission for Asia and the Pacific (ESCAP) region, using available data and frequently applied indices such as the population pyramid, aged-child ratio, and median age. Based on the overall picture of the age structure thus obtained, age trends and their implication for the near future were arrived at. Countries are grouped into 4 types based on the fertility and mortality levels. Except for Japan, Hong Kong, and Singapore, the age structure in the 18 ESCAP region countries changed comparatively little over the 1950-80 period. The largest structural change occurred in Singapore, where the proportion of children under age 15 in the population declined significantly from 41-27%, while that of persons 65 years and older more than doubled. This was due primarily to the marked decline in fertility from a total fertility rate (TFR) of 6.7-1.8 during the period. Hong Kong also had a similar major transformation during the same period: the proportion of the old age population increased 2 1/2 times, from 2.5-6.3%. The age structures of the 18 ESCAP countries varied greatly by country. 10 countries of the 2 high fertility and mortality types showed a similar young age structural pattern, i.e., they have higher dependency ratios, a higher proportion of children under 15 years, a lower proportion of population 65 years and older, lower aged-child ratios, and younger median ages than the average countries in the less developed regions of the world. With minimal changes over the 1950-80 period, the gap between these countries and the average of the less developed regions widened. Unlike these 10 (mostly South Asian) countries, moderately low fertility and mortality countries (China, Korea, and Sri Lanka) are located between the world average and the less developed region in most of the indices, particularly during the last decade. Although their rate of population aging is not

  12. Escape trajectories of solar sails and general relativity

    International Nuclear Information System (INIS)

    Kezerashvili, Roman Ya.; Vazquez-Poritz, Justin F.

    2009-01-01

    General relativity can have a significant impact on the long-range escape trajectories of solar sails deployed near the sun. For example, spacetime curvature in the vicinity of the sun can cause a solar sail traveling from about 4 solar radii to 2550 AU to be deflected by on the order of a million kilometers, and should therefore be taken into account at the beginning of the mission. There are a number of smaller general relativistic effects, such as frame dragging due to the slow rotation of the sun which can cause a deflection of more than one thousand kilometers.

  13. International Environmental Agreements: Emissions Trade, Safety Valves and Escape Clauses

    International Nuclear Information System (INIS)

    Karp, Larry; Zhao, Jinhua

    2010-01-01

    We explain how the structure of multi-national or multi-regional environmental agreements affect their chance of success. Trade in emissions permits has ambiguous and in some cases surprising effects on both the equilibrium level of abatement, and on the ability to persuade nations or regions to participate in environmental agreements. An escape clause policy and a safety valve policy have essentially the same properties when membership in environmental agreement is pre-determined, but they create markedly different effects on the incentives to join such an agreement. The two policies lead to a qualitative difference in the leverage that a potential member of the agreement exercises on other members

  14. The case of escape probability as linear in short time

    Science.gov (United States)

    Marchewka, A.; Schuss, Z.

    2018-02-01

    We derive rigorously the short-time escape probability of a quantum particle from its compactly supported initial state, which has a discontinuous derivative at the boundary of the support. We show that this probability is linear in time, which seems to be a new result. The novelty of our calculation is the inclusion of the boundary layer of the propagated wave function formed outside the initial support. This result has applications to the decay law of the particle, to the Zeno behaviour, quantum absorption, time of arrival, quantum measurements, and more.

  15. Mechanisms of Pulmonary Escape and Dissemination by Cryptococcus neoformans

    Directory of Open Access Journals (Sweden)

    Steven T. Denham

    2018-02-01

    Full Text Available Cryptococcus neoformans is a common environmental saprophyte and human fungal pathogen that primarily causes disease in immunocompromised individuals. Similar to many environmentally acquired human fungal pathogens, C. neoformans initiates infection in the lungs. However, the main driver of mortality is invasive cryptococcosis leading to fungal meningitis. After C. neoformans gains a foothold in the lungs, a critical early step in invasion is transversal of the respiratory epithelium. In this review, we summarize current knowledge relating to pulmonary escape. We focus on fungal factors that allow C. neoformans to disseminate from the lungs via intracellular and extracellular routes.

  16. European SpaceCraft for the study of Atmospheric Particle Escape (ESCAPE): a planetary mission to Earth, proposed in response to the ESA M5-call

    Science.gov (United States)

    Dandouras, I.; Yamauchi, M.; Rème, H.; De Keyser, J.; Marghitu, O.; Fazakerley, A.; Grison, B.; Kistler, L.; Milillo, A.; Nakamura, R.; Paschalidis, N.; Paschalis, A.; Pinçon, J.-L.; Sakanoi, T.; Wieser, M.; Wurz, P.; Yoshikawa, I.; Häggström, I.; Liemohn, M.; Tian, F.

    2017-09-01

    ESCAPE is a mission proposed in response to the ESA-M5 call that will quantitatively estimate the amount of escaping particles of the major atmospheric components (nitrogen and oxygen), as neutral and ionised species, escaping from the Earth as a magnetised planet. The goal is to understand the importance of each escape mechanism, its dependence on solar and geomagnetic activity, and to infer the history of the Earth's atmospheric composition over a long (geological scale) time period. Since the solar EUV and solar wind conditions during solar maximum at present are comparable to the solar minimum conditions 1-2 billion years ago, the escaping amount and the isotope and N/O ratios should be obtained as a function of external forcing (solar and geomagnetic conditions) to allow a scaling to the past. The result will be used as a reference to understand the atmospheric/ionospheric evolution of magnetised planets, which is essential for habitability.

  17. Thymus Atrophy and Double-Positive Escape Are Common Features in Infectious Diseases

    Directory of Open Access Journals (Sweden)

    Juliana de Meis

    2012-01-01

    Full Text Available The thymus is a primary lymphoid organ in which bone marrow-derived T-cell precursors undergo differentiation, leading to migration of positively selected thymocytes to the T-cell-dependent areas of secondary lymphoid organs. This organ can undergo atrophy, caused by several endogenous and exogenous factors such as ageing, hormone fluctuations, and infectious agents. This paper will focus on emerging data on the thymic atrophy caused by infectious agents. We present data on the dynamics of thymus lymphocytes during acute Trypanosoma cruzi infection, showing that the resulting thymus atrophy comprises the abnormal release of thymic-derived T cells and may have an impact on host immune response.

  18. New insights on the collisional escape of light neutrals from Mars

    Science.gov (United States)

    Gacesa, Marko; Zahnle, Kevin

    2017-04-01

    Photodissociative recombination (PDR) of atmospheric molecules on Mars is a major mechanism of production of hot (suprathermal) atoms with sufficient kinetic energy to either directly escape to space or to eject other atmospheric species. This collisional ejection mechanism is important for evaluating the escape rates of all light neutrals that are too heavy to escape via Jeans escape. In particular, it plays a role in estimating the total volume of escaped water constituents (i.e., O and H) from Mars, as well as influences evolution of the atmospheric [D]/[H] ratio1. We present revised estimates of total collisional escape rates of neutral light elements including H, He, and H2, based on recent (years 2015-2016) atmospheric density profiles obtained from the NASA Mars Atmosphere and Volatile Evolution (MAVEN) mission. We also estimate the contribution to the collisional escape from Energetic Neutral Atoms (ENAs) produced in charge-exchange of solar wind H+ and He+ ions with atmospheric gases2,3. Scattering of hot oxygen and atmospheric species of interest is modeled using fully-quantum reactive scattering formalism1,3. The escape rates are evaluated using a 1D model of the atmosphere supplemented with MAVEN measurements of the neutrals. Finally, new estimates of contributions of these non-thermal mechanisms to the estimated PDR escape rates from young Mars4 are presented. [1] M. Gacesa and V. Kharchenko, "Non-thermal escape of molecular hydrogen from Mars", Geophys. Res. Lett., 39, L10203 (2012). [2] N. Lewkow and V. Kharchenko, "Precipitation of Energetic Neutral Atoms and Escape Fluxes induced from the Mars Atmosphere", Astroph. J., 790, 98 (2014). [3] M. Gacesa, N. Lewkow, and V. Kharchenko, "Non-thermal production and escape of OH from the upper atmosphere of Mars", Icarus 284, 90 (2017). [4] J. Zhao, F. Tian, Y. Ni, and X. Huang, "DR-induced escape of O and C from early Mars", Icarus 284, 305 (2017).

  19. Ontogeny of thymic independent antibody responses in vitro in normal mice and mice with an x-linked B cell defect

    Energy Technology Data Exchange (ETDEWEB)

    Mosier, D.E.; Mond, J.J.; Goldings, E.A.

    1977-12-01

    The primary in vitro antibody response of neonatal spleen cells to three thymic independent antigens has been examined. The time of onset of responsiveness to TNP-Brucella abortus and TNP-lipopolysaccharide was significantly earlier than the onset of responsiveness to TNP-Ficoll. This ontologic sequence was not affected by T cell depletion or antigen presentation on adult macrophages. In neonatal mice bearing the X-linked CBA/N defect, the response to TNP-Brucella abortus and TNP-lipopolysaccharide was much delayed and no response to TNP-Ficoll developed. We conclude that different thymic independent antigens address different subpopulations of B cells, one of which appears earlier in ontogeny than the other.

  20. Nur77 nuclear import and its NBRE-binding activity in thymic lymphoma cells are regulated by different mechanisms sensitive to FK506 or HA1004

    International Nuclear Information System (INIS)

    Kochel, Izabela; Rapak, Andrzej; Ziolo, Ewa; Strzadala, Leon

    2005-01-01

    Thymic lymphoma cells restore their sensitivity to ionomycin-induced apoptosis when treated with FK506 or HA1004. In apoptosis-resistant cells, ionomycin-induced Nur77 strongly binds DNA during the first 2 h of response, in contrast to lymphoma cells treated with ionomycin together with FK506 or HA1004, which undergo massive apoptosis. We show that Nur77 could discriminate between calcium signals sensitive to FK506 and those sensitive to HA1004, as the inhibitors differentially regulate the kinetics of Nur77 nuclear import, and FK506, unlike HA1004, inhibits Nur77 DNA-binding activity. In the presence of HA1004, NBRE binding by Nur77 protein increases with time (6 h vs 2 h), whereas the final outcome of both inhibitors is apoptosis of thymic lymphoma cells

  1. Ontogeny of thymic independent antibody responses in vitro in normal mice and mice with an x-linked B cell defect

    International Nuclear Information System (INIS)

    Mosier, D.E.; Mond, J.J.; Goldings, E.A.

    1977-01-01

    The primary in vitro antibody response of neonatal spleen cells to three thymic independent antigens has been examined. The time of onset of responsiveness to TNP-Brucella abortus and TNP-lipopolysaccharide was significantly earlier than the onset of responsiveness to TNP-Ficoll. This ontologic sequence was not affected by T cell depletion or antigen presentation on adult macrophages. In neonatal mice bearing the X-linked CBA/N defect, the response to TNP-Brucella abortus and TNP-lipopolysaccharide was much delayed and no response to TNP-Ficoll developed. We conclude that different thymic independent antigens address different subpopulations of B cells, one of which appears earlier in ontogeny than the other

  2. On the escape of pollutants from urban street canyons

    Energy Technology Data Exchange (ETDEWEB)

    Baik, J.J.; Kim, J.J. [Kwangju Inst. of Science and Technology (Korea). Dept. of Environmental Science and Engineering

    2002-07-01

    Pollutant transport from urban street canyons is numerically investigated using a two-dimensional flow and dispersion model. The ambient wind blows perpendicular to the street and passive pollutants are released at the street level. Results from the control experiment with a street aspect ratio of 1 show that at the roof level of the street canyon, the vertical turbulent flux of pollutants is upward everywhere and the vertical flux of pollutants by mean flow is upward or downward. The horizontally integrated vertical flux of pollutants by mean flow at the roof level of the street canyon is downward and its magnitude is much smaller than that by turbulent process. These results indicate that pollutants escape from the street canyon mainly by turbulent process and that the net effect of mean flow is to make some escaped pollutants reenter the street canyon. Further experiments with different inflow turbulence intensities, inflow wind speeds, and street aspect ratio confirm the findings from the control experiment. In the case of two isolated buildings, the horizontally integrated vertical flux of pollutants by mean flow is upward due to flow separation but the other main results are the same as those from the control experiment. (author)

  3. Ultra-fast Escape of a Octopus-inspired Rocket

    Science.gov (United States)

    Weymouth, Gabriel; Triantafyllou, Michael

    2013-11-01

    The octopus, squid, and other cephalopods inflate with water and then release a jet to accelerate in the opposite direction. This escape mechanism is particularly interesting in the octopus because they become initially quite bluff, yet this does not hinder them in achieving impressive bursts of speed. We examine this somewhat paradoxical maneuver using a simple deflating spheroid model in both potential and viscous flow. We demonstrate that the dynamic reduction of the width of the body completely changes the flow and forces acting on the escaping rocket in three ways. First, a body which reduces in size can generate an added mass thrust which counteracts the added mass inertia. Second, the motion of the shrinking wall acts similar to suction on a static wall, reducing separation and drag forces in a viscous fluid, but that this effects depends on the rate of size change. Third, using a combination of these two features it is possible to initially load the fluid with kinetic energy when heavy and bluff and then recover that energy when streamlined and light, enabling ultra-fast accelerations. As a notable example, these mechanisms allow a shrinking spheroid rocket in a heavy inviscid fluid to achieve speeds greater than an identical rocket in the vacuum of space. Southampton Marine and Maritime Institute.

  4. Lionfish misidentification circumvents an optimized escape response by prey.

    Science.gov (United States)

    McCormick, Mark I; Allan, Bridie J M

    2016-01-01

    Invasive lionfish represent an unprecedented problem in the Caribbean basin, where they are causing major changes to foodwebs and habitats through their generalized predation on fishes and invertebrates. To ascertain what makes the red lionfish ( Pterois volitans ) such a formidable predator, we examined the reaction of a native damselfish prey, the whitetail damsel ( Pomacentrus chrysurus ), to a repeatable startle stimulus once they had been forewarned of the sight or smell of lionfish. Fast-start responses were compared with prey forewarned of a predatory rockcod ( Cephalopholis microprion ), a corallivorous butterflyfish ( Chaetodon trifasctiatus ) and experimental controls. Forewarning of the sight, smell or a combination of the two cues from a rockcod led to reduced escape latencies and higher response distances, speed and maximal speed compared with controls, suggesting that forewarning primed the prey and enabled a more effective escape response. In contrast, forewarning of lionfish did not affect the fast-start kinematics measured, which were the same as in the control and non-predatory butterflyfish treatments. Lionfish appear to be able to circumvent mechanisms commonly used by prey to identify predators and were misclassified as non-predatory, and this is likely to contribute to their success as predators.

  5. Escape of charged particles from a neutron star

    International Nuclear Information System (INIS)

    Pelizzari, M.A.

    1976-01-01

    The theory of particle trajectories in an axisymmetric magnetic field, formulated by C. Stormer, can be extended to cover conservative force fields as well. As such, it is an ideal tool to study the escape of charged particles from a rapidly rotating neutron star, enabling one to determine the maximum range of their trajectories in space. With the aid of this theory, it is shown that a neutron star, rotating in a vacuum with rotation and magnetic axes aligned, will not evolve a perfectly conducting magnetosphere if the neutron star is the only source of charge. The sign of charge accelerated from the equatorial regions will be magnetically trapped to a toroidal region very near the star, and the opposite sign of charge, emerging from the polar regions, will escape from the magnetosphere until a critical stellar charge is reached, after which polar charges will be electrostatically bound to the magnetosphere. This selective magnetic trapping of one sign of charge, which prevents the formation of a stellar wind, is a consequence of the magnetic field's orientation relative to the internal charge density of the neutron star

  6. Cyclosporine promotes the induction of thymic lymphomas in C57BL/6 mice initiated by a single dose of γ-radiation

    International Nuclear Information System (INIS)

    Yabu, Koji; Warty, V.S.; Gorelik, E.; Shinozuka, Hisashi

    1991-01-01

    We previously demonstrated that a single dose of γ-radiation (350 rads) was able to induce thymic lymphomas in C57BL mice when followed by promoting treatment with oral cyclosporine (CsA), a non-genotoxic immunosuppressant. We have now tested the efficacy of various doses of γ-radiation as an initiator of CsA promotion of the induction of thymic lymphomas in male C57BL mice. The effects of oral CsA on the splenic natural killer (NK) cell activity of non-irradiated and irradiated (400 rads, 1X) mice were tested by the standard 51 Cr release assays against YAC-1 cells. The cumulative incidence of thymic lymphomas induced by a single dose of γ-radiation at 100, 200, 400 and 600 rads were 10, 25, 63 and 75% respectively, after 42 weeks of CsA promotion. The splenic NK cell activity in non-irradiated mice given CsA for 4 weeks was twice as high as that in the control mice. CsA inhibited poly I:C-induced augmentation of the splenic NK cell activity. In mice given a single dose (400 rads) of γ-radiation and CsA for 4 weeks, a similar but reduced enhancement of the splenic NK cell activity as seen in non-irradiated mice was observed. These results indicate that the efficacy of CsA promotion in the induction of thymic lymphomas is dependent on the initiating doses of γ-radiation, and that CsA enhances host splenic NK cell activity during the early stage of tumor promotion. (author)

  7. The actin regulator coronin-1A is mutated in a thymic egress deficient mouse strain and in a T?B+NK+ SCID patient

    OpenAIRE

    Shiow, Lawrence R.; Roadcap, David W.; Paris, Kenneth; Watson, Susan R.; Grigorova, Irina L.; Lebet, Tonya; An, Jinping; Xu, Ying; Jenne, Craig N.; F?ger, Niko; Sorensen, Ricardo U.; Goodnow, Christopher C.; Bear, James E.; Puck, Jennifer M.; Cyster, Jason G.

    2008-01-01

    Mice carrying the recessive peripheral T cell deficiency (Ptcd) locus have a block in thymic egress but the mechanism responsible is undefined. Here we found that Ptcd T cells have an intrinsic migration defect, impaired lymphoid tissue trafficking and irregularly shaped protrusions. Characterization of the Ptcd locus revealed an E26K point mutation within the actin regulator coronin-1A (Coro1a) that enhanced its inhibition of the actin regulator Arp2/3 and resulted in its mislocalization fro...

  8. Effect of Boron on Thymic Cytokine Expression, Hormone Secretion, Antioxidant Functions, Cell Proliferation, and Apoptosis Potential via the Extracellular Signal-Regulated Kinases 1 and 2 Signaling Pathway.

    Science.gov (United States)

    Jin, Erhui; Ren, Man; Liu, Wenwen; Liang, Shuang; Hu, Qianqian; Gu, Youfang; Li, Shenghe

    2017-12-27

    Boron is an essential trace element in animals. Appropriate boron supplementation can promote thymus development; however, a high dose of boron can lead to adverse effects and cause toxicity. The influencing mechanism of boron on the animal body remains unclear. In this study, we examined the effect of boron on cytokine expression, thymosin and thymopoietin secretion, antioxidant function, cell proliferation and apoptosis, and extracellular signal-regulated kinases 1 and 2 (ERK1/2) pathway in the thymus of rats. We found that supplementation with 10 and 20 mg/L boron to the drinking water significantly elevated levels of interleukin 2 (IL-2), interferon γ (IFN-γ), interleukin 4 (IL-4), and thymosin α1 in the thymus of rats (p boron had no apparent effect on many of the above indicators. In contrast, supplementation with 480 and 640 mg/L boron had the opposite effect on the above indicators in rats and elevated levels of pro-inflammatory cytokines, such as interleukin 6 (IL-6), interleukin 1β (IL-1β), and tumor necrosis factor α (TNF-α) (p boron to the drinking water had a U-shaped dose-effect relationship with thymic cytokine expression, hormone secretion, antioxidant function, cell proliferation, and apoptosis. Specifically, supplementation with 10 and 20 mg/L boron promoted thymocyte proliferation and enhanced thymic functions. However, supplementation with 480 and 640 mg/L boron inhibited thymic functions and increased the number of apoptotic thymocytes, suggesting that the effects of boron on thymic functions may be caused via the ERK1/2 signaling pathway.

  9. The Tec kinase ITK regulates thymic expansion, emigration, and maturation of γδ NKT cells.

    Science.gov (United States)

    Yin, Catherine C; Cho, Ok Hyun; Sylvia, Katelyn E; Narayan, Kavitha; Prince, Amanda L; Evans, John W; Kang, Joonsoo; Berg, Leslie J

    2013-03-15

    The Tec family tyrosine kinase, Itk, regulates signaling downstream of the TCR. The absence of Itk in CD4(+) T cells results in impaired Th2 responses along with defects in maturation, cytokine production, and survival of iNKT cells. Paradoxically, Itk(-/-) mice have spontaneously elevated serum IgE levels, resulting from an expansion of the Vγ1.1(+)Vδ6.3(+) subset of γδ T cells, known as γδ NKT cells. Comparisons between γδ NKT cells and αβ iNKT cells showed convergence in the pattern of cell surface marker expression, cytokine profiles, and gene expression, suggesting that these two subsets of NKT cells undergo similar differentiation programs. Hepatic γδ NKT cells have an invariant TCR and are derived predominantly from fetal progenitors that expand in the thymus during the first weeks of life. The adult thymus contains these invariant γδ NKT cells plus a heterogeneous population of Vγ1.1(+)Vδ6.3(+) T cells with diverse CDR3 sequences. This latter population, normally excluded from the liver, escapes the thymus and homes to the liver when Itk is absent. In addition, Itk(-/-) γδ NKT cells persistently express high levels of Zbtb16 (PLZF) and Il4, genes that are normally downregulated in the most mature subsets of NKT cells. These data indicate that Itk signaling is required to prevent the expansion of γδ NKT cells in the adult thymus, to block their emigration, and to promote terminal NKT cell maturation.

  10. Deletion of Notch1 converts pro-T cells to dendritic cells and promotes thymic B cells by cell-extrinsic and cell-intrinsic mechanisms.

    Science.gov (United States)

    Feyerabend, Thorsten B; Terszowski, Grzegorz; Tietz, Annette; Blum, Carmen; Luche, Hervé; Gossler, Achim; Gale, Nicholas W; Radtke, Freddy; Fehling, Hans Jörg; Rodewald, Hans-Reimer

    2009-01-16

    Notch1 signaling is required for T cell development and has been implicated in fate decisions in the thymus. We showed that Notch1 deletion in progenitor T cells (pro-T cells) revealed their latent developmental potential toward becoming conventional and plasmacytoid dendritic cells. In addition, Notch1 deletion in pro-T cells resulted in large numbers of thymic B cells, previously explained by T-to-B cell fate conversion. Single-cell genotyping showed, however, that the majority of these thymic B cells arose from Notch1-sufficient cells by a cell-extrinsic pathway. Fate switching nevertheless exists for a subset of thymic B cells originating from Notch1-deleted pro-T cells. Chimeric mice lacking the Notch ligand delta-like 4 (Dll4) in thymus epithelium revealed an essential role for Dll4 in T cell development. Thus, Notch1-Dll4 signaling fortifies T cell commitment by suppressing non-T cell lineage potential in pro-T cells, and normal Notch1-driven T cell development repels excessive B cells in the thymus.

  11. Inhibitory effects of a polypeptide thymic factor on the development of 7,12-dimethylbenz(a)anthragene-induced mammary adenocarcinoma in female rats

    Energy Technology Data Exchange (ETDEWEB)

    Anisimov, V.N.; Danetskaya, E.V.; Morozov, V.G.; Khavinson, V.Kh.

    1980-01-01

    It has come to be recognized that tumor growth is accompanied by inhibition of cellular immunity and the function of the T lymphocytes. Restitution of T lymphocyte function by means of several pharmacologic agents such as levamisole, phenformin, or epithalamin (an epiphyseal factor) has, in a number of cases, been accompanied by growth inhibition of both spontaneous and induced tumors. In addition, the importance of the thymus in the regulation of T lymphocytes and in antitumor immunity has been recognized. Several indicators point to the fact that the thymus contains physiologically active substances which stimulate T cell-dependent immunity and prevent the occurrence of neoplasms. These considerations have led to attempts at isolation of active thymic factors and studies on their effects on the appearance and growth of tumors. Previously, a thymic factor - thymarin - had been isolated which imparted immunocompetence to the T lymphocytes. This factor differs from other thymic preparations, including thymosine, in terms of a number of physicochemical characteristics and is a polypeptide with a molecular weight of 5000. This study is concerned with its effects on tumor development - mammary gland adenocarcinoma induced in animals with a chemical carcinogen.

  12. Orbital and escape dynamics in barred galaxies - III. The 3D system: correlations between the basins of escape and the NHIMs

    Science.gov (United States)

    Zotos, Euaggelos E.; Jung, Christof

    2018-01-01

    The escape dynamics of the stars in a barred galaxy composed of a spherically symmetric central nucleus, a bar, a flat thin disc and a dark matter halo component is investigated by using a realistic three degrees of freedom (3-d.o.f.) dynamical model. Modern colour-coded diagrams are used for distinguishing between bounded and escaping motion. In addition, the smaller alignment index method is deployed for determining the regular, sticky or chaotic nature of bounded orbits. We reveal the basins of escape corresponding to the escape through the two symmetrical escape channels around the Lagrange points L2 and L3 and also we relate them with the corresponding distribution of the escape times of the orbits. Furthermore, we demonstrate how the stable manifolds, around the index-1 saddle points, accurately define the fractal basin boundaries observed in the colour-coded diagrams. The development scenario of the fundamental vertical Lyapunov periodic orbit is thoroughly explored for obtaining a more complete view of the unfolding of the singular behaviour of the dynamics at the cusp values of the parameters. Finally, we examine how the combination of the most important parameters of the bar (such as the semimajor axis and the angular velocity) influences the observed stellar structures (rings and spirals), which are formed by escaping stars guided by the invariant manifolds near the saddle points.

  13. Integrating geographical information and augmented reality techniques for mobile escape guidelines on nuclear accident sites

    International Nuclear Information System (INIS)

    Tsai, Ming-Kuan; Lee, Yung-Ching; Lu, Chung-Hsin; Chen, Mei-Hsin; Chou, Tien-Yin; Yau, Nie-Jia

    2012-01-01

    During nuclear accidents, when radioactive materials spread into the environment, the people in the affected areas should evacuate immediately. However, few information systems are available regarding escape guidelines for nuclear accidents. Therefore, this study constructs escape guidelines on mobile phones. This application is called Mobile Escape Guidelines (MEG) and adopts two techniques. One technique is the geographical information that offers multiple representations; the other is the augmented reality that provides semi-realistic information services. When this study tested the mobile escape guidelines, the results showed that this application was capable of identifying the correct locations of users, showing the escape routes, filtering geographical layers, and rapidly generating the relief reports. Users could evacuate from nuclear accident sites easily, even without relief personnel, since using slim devices to access the mobile escape guidelines is convenient. Overall, this study is a useful reference for a nuclear accident emergency response.

  14. Integrating geographical information and augmented reality techniques for mobile escape guidelines on nuclear accident sites.

    Science.gov (United States)

    Tsai, Ming-Kuan; Lee, Yung-Ching; Lu, Chung-Hsin; Chen, Mei-Hsin; Chou, Tien-Yin; Yau, Nie-Jia

    2012-07-01

    During nuclear accidents, when radioactive materials spread into the environment, the people in the affected areas should evacuate immediately. However, few information systems are available regarding escape guidelines for nuclear accidents. Therefore, this study constructs escape guidelines on mobile phones. This application is called Mobile Escape Guidelines (MEG) and adopts two techniques. One technique is the geographical information that offers multiple representations; the other is the augmented reality that provides semi-realistic information services. When this study tested the mobile escape guidelines, the results showed that this application was capable of identifying the correct locations of users, showing the escape routes, filtering geographical layers, and rapidly generating the relief reports. Users could evacuate from nuclear accident sites easily, even without relief personnel, since using slim devices to access the mobile escape guidelines is convenient. Overall, this study is a useful reference for a nuclear accident emergency response. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Gamma-ray escape peak characteristics of radiation-damaged reverse-electrode germanium coaxial detectors

    International Nuclear Information System (INIS)

    Pehl, R.H.; Hull, E.L.; Madden, N.W.; Xing Jingshu; Friesel, D.L.

    1996-01-01

    A comparison of the characteristics of full-energy gamma-ray peaks and their corresponding escape peaks when high energy photons interact in radiation damaged reverse-electrode (n-type) germanium coaxial detectors is presented. Coaxial detector geometry is the dominant factor, causing charge collection to be dramatically better for interactions occurring near the outer periphery of the detector as well as increasing of the probability of escape events occurring in this region. It follows that the resolution of escape peaks is better than that of ordinary gamma-ray peaks. This is experimentally verified. A nearly identical but undamaged detector exhibited significant Doppler broadening of single escape peaks. Because double escape events preferentially occur at outer radii, energy shifts of double escape reflect extremely small amounts of charge trapping in undamaged detectors. (orig.)

  16. Escaping Electrons from Intense Laser-Solid Interactions as a Function of Laser Spot Size

    OpenAIRE

    Rusby, Dean; Gray, Ross; Butler, Nick; Dance, Rachel; Scott, Graeme; Bagnoud, Vincent; Zielbauer, Bernhard; McKenna, Paul; Neely, David

    2018-01-01

    The interaction of a high-intensity laser with a solid target produces an energetic distribution of electrons that pass into the target. These electrons reach the rear surface of the target creating strong electric potentials that act to restrict the further escape of additional electrons. The measurement of the angle, flux and spectra of the electrons that do escape gives insights to the initial interaction. Here, the escaping electrons have been measured using a differentially filtered imag...

  17. On the relative contributions of positive reinforcement and escape extinction in the treatment of food refusal.

    OpenAIRE

    Piazza, Cathleen C; Patel, Meeta R; Gulotta, Charles S; Sevin, Bari M; Layer, Stacy A

    2003-01-01

    We compared the effects of positive reinforcement alone, escape extinction alone, and positive reinforcement with escape extinction in the treatment of the food and fluid refusal of 4 children who had been diagnosed with a pediatric feeding disorder. Consumption did not increase when positive reinforcement was implemented alone. By contrast, consumption increased for all participants when escape extinction was implemented, independent of the presence or absence of positive reinforcement. Howe...

  18. Is a positron emission tomography-computed tomography scan useful in the staging of thymic epithelial neoplasms?

    Science.gov (United States)

    Viti, Andrea; Terzi, Alberto; Bianchi, Andrea; Bertolaccini, Luca

    2014-07-01

    A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed concerned the employment of 18-fluorine fluorodeoxyglucose positron emission tomography/computed tomography (PET-CT) in the preoperative evaluation of thymic epithelial neoplasms (TENs). We reviewed its role as a predictor of Masaoka stage and histology (according to the WHO). In clinical practice, stage is considered the most important determinant in the therapeutic approach. A total of 265 papers were found as a result of the reported search, of which 14 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. All the studies are retrospective analyses. Patient numbers varied from 13 to 58. Our research showed that PET-CT could clearly add information about the histology of the tumour. Thymic carcinoma constantly showed a higher standard uptake value (SUVmax) than thymomas. Furthermore, in one retrospective study of 36 patients, when using a derived PET indicator, the T/M ratio (ratio between SUVmax of the tumour and SUVmax of mediastinum, as conventionally measured at the level of the aortic arc), PET-CT could also differentiate between low- and high-risk thymomas (low risk vs high risk P = 0.01). In another study, a cut-off value of T/M ratio of 2.75 was identified between low- and high-risk TENs. The role of PET-CT in prediction of stage is harder to recognize. In one study, there was a statistically significant correlation between SUVmax, T/M ratio and Masaoka stage (P = 0.781 and 0.718, respectively). When analysing the data from the three larger series on this topic (58, 51 and 47 patients, the latter group selected in a multicentre study), only one study identified a correlation between SUVmax and Masaoka stage (Spearman correlation coefficient 0.30, P = 0.0436), while the other two failed

  19. Correlation between the CT manifestations and post-operative survival time in patients with thymic epithelial tumor

    International Nuclear Information System (INIS)

    Chen Juan; Tan Ye; Wang Xiangyang; Du Jun; Pan Jishu; Wei Jiahu

    2011-01-01

    Objective: To describe the CT manifestations of thymic epithelial tumor and explore the correlation between CT findings and post-operative tumor-related survival time. Methods: Ninety-one patients who underwent CT scan before operation were reviewed retrospectively. All cases had operation and were classified according to the WHO classification. The size, contour, shape, density and enhancement of the tumors on CT were assessed. Presence of mediastinal lymphadenopathy, great vessel invasion, metastasis to the lung or plural, myasthenia gravis (MG) were also analyzed. The survival rate was obtained using, the Kaplan-Meier method. The Cox model was applied to determine the factors affecting the tumor-related survivals. Chi square test was used to analyze the relationship between CT findings and WHO classification. Results: Two patients were excluded because of dying of myocardial infarction and colon cancer. The total 5-year survival rate was 84.3% (n=75). Eighty-nine patients had total 91 tumors. Tumors with diameter larger than 5 cm, lobular contour, heterogenous density, and presence of great vessel invasion, mediastinal lymphadenopathy, and metastasis were adverse factors which could significantly affect the survival time. Five-year survival rates of these factors were 72.7%, 77.3%, 76.7%, 73.8%, 30.0%, and 68.8%, respectively. Presence of MG was a favorable factor which also significantly affected the survival time (P 0.05). The result of the Cox multivariate analysis was consistent with that of the Log-rank test. For different WHO classification, there were significant different among the size or contour of the tumors, presence of great vessel invasion, mediastinal lymphadenopathy, and metastasis (χ 2 value were 6.598, 5.737, 18.307, 8.465, and 15.608, respectively P<0.05). Conclusions: CT findings may be served as predictors of clinical prognosis of the thymic epithelial tumors. Adverse factors for survival time are the size of the tumors and presence of

  20. Effects of 2,3,7,8-TCDD and PCB 126 on human thymic epithelial cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Riecke, Kai [Institut fuer Klinische Pharmakologie und Toxikologie (Abt. Toxikologie), Universitaetsklinikum Benjamin Franklin, Freie Universitaet Berlin, Garystrasse 5, 14195, Berlin (Germany); Experimental Toxicology, Schering AG, 10334, Berlin (Germany); Schmidt, Andre; Stahlmann, Ralf [Institut fuer Klinische Pharmakologie und Toxikologie (Abt. Toxikologie), Universitaetsklinikum Benjamin Franklin, Freie Universitaet Berlin, Garystrasse 5, 14195, Berlin (Germany)

    2003-06-01

    2,3,7,8-Tetrachloro-dibenzo-p-dioxin (TCDD) is a ubiquitously distributed xenobiotic. The adverse effects of TCDD on the mammalian immune system have been studied for decades, but it is still unclear whether TCDD has direct effects on T-lymphocytes or whether it acts via the thymic microenvironment. We have studied the effects of TCDD on primary cultures of human thymic epithelial cells (TEC) focusing on differentiation markers, integrins and adhesion molecules involved in cell-cell and in cell-matrix interactions. TEC were treated with TCDD at concentrations of 0.001, 0.01, 0.1, 1.0 or 10.0 nM or with 100 nM PCB 126 (3,3',4,4',5-pentachlorobiphenyl) for 3 days, and were then analysed by flow cytometry for expression of surface antigens using monoclonal antibodies against Hassall's bodies (TE-8, TE-16) or against surface structures such as CD29, CD49b, CD49e, CD49f, CD51, CD54, CD58, CD61 and CD106. At TCDD concentrations as low as 0.01 nM we found a significant increase in terminally differentiated, TE-16-positive TEC; at a ten-fold greater concentration the number of cells marked with the TE-8 antibody was also increased. With both markers the most pronounced effect (approximately +15%) was observed at 1 nM TCDD. An increase of cells expressing the integrin {alpha}-chains CD49b, CD49e and CD51 as well as CD54 was observed at concentrations of 0.1 nM TCDD or higher. The proportion of cells expressing CD106 or CD49f decreased significantly upon treatment with TCDD. No effects on the integrin {beta}-chains CD29 and CD61 could be detected. Overall, PCB 126 induced similar changes to TCDD. In summary, TCDD and a coplanar PCB induced terminal differentiation of human TEC along with changes of integrins and other adhesion molecules. These receptors and their interplay with the extracellular matrix have key functions in the maturation of T-lymphocytes and it is plausible that their alteration would be involved in TCDD-induced immunotoxicity. (orig.)

  1. The Escape of Cancer from T Cell-Mediated Immune Surveillance: HLA Class I Loss and Tumor Tissue Architecture

    Directory of Open Access Journals (Sweden)

    Federico Garrido

    2017-02-01

    Full Text Available Tumor immune escape is associated with the loss of tumor HLA class I (HLA-I expression commonly found in malignant cells. Accumulating evidence suggests that the efficacy of immunotherapy depends on the expression levels of HLA class I molecules on tumors cells. It also depends on the molecular mechanism underlying the loss of HLA expression, which could be reversible/“soft” or irreversible/“hard” due to genetic alterations in HLA, β2-microglobulin or IFN genes. Immune selection of HLA-I negative tumor cells harboring structural/irreversible alterations has been demonstrated after immunotherapy in cancer patients and in experimental cancer models. Here, we summarize recent findings indicating that tumor HLA-I loss also correlates with a reduced intra-tumor T cell infiltration and with a specific reorganization of tumor tissue. T cell immune selection of HLA-I negative tumors results in a clear separation between the stroma and the tumor parenchyma with leucocytes, macrophages and other mononuclear cells restrained outside the tumor mass. Better understanding of the structural and functional changes taking place in the tumor microenvironment may help to overcome cancer immune escape and improve the efficacy of different immunotherapeutic strategies. We also underline the urgent need for designing strategies to enhance tumor HLA class I expression that could improve tumor rejection by cytotoxic T-lymphocytes (CTL.

  2. Antibody escape kinetics of equine infectious anemia virus infection of horses.

    Science.gov (United States)

    Schwartz, Elissa J; Nanda, Seema; Mealey, Robert H

    2015-07-01

    Lentivirus escape from neutralizing antibodies (NAbs) is not well understood. In this work, we quantified antibody escape of a lentivirus, using antibody escape data from horses infected with equine infectious anemia virus. We calculated antibody blocking rates of wild-type virus, fitness costs of mutant virus, and growth rates of both viruses. These quantitative kinetic estimates of antibody escape are important for understanding lentiviral control by antibody neutralization and in developing NAb-eliciting vaccine strategies. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  3. Sharks modulate their escape behavior in response to predator size, speed and approach orientation.

    Science.gov (United States)

    Seamone, Scott; Blaine, Tristan; Higham, Timothy E

    2014-12-01

    Escape responses are often critical for surviving predator-prey interactions. Nevertheless, little is known about how predator size, speed and approach orientation impact escape performance, especially in larger prey that are primarily viewed as predators. We used realistic shark models to examine how altering predatory behavior and morphology (size, speed and approach orientation) influences escape behavior and performance in Squalus acanthias, a shark that is preyed upon by apex marine predators. Predator models induced C-start escape responses, and increasing the size and speed of the models triggered a more intense response (increased escape turning rate and acceleration). In addition, increased predator size resulted in greater responsiveness from the sharks. Among the responses, predator approach orientation had the most significant impact on escapes, such that the head-on approach, as compared to the tail-on approach, induced greater reaction distances and increased escape turning rate, speed and acceleration. Thus, the anterior binocular vision in sharks renders them less effective at detecting predators approaching from behind. However, it appears that sharks compensate by performing high-intensity escapes, likely induced by the lateral line system, or by a sudden visual flash of the predator entering their field of view. Our study reveals key aspects of escape behavior in sharks, highlighting the modulation of performance in response to predator approach. Copyright © 2014 Elsevier GmbH. All rights reserved.

  4. Decompression illness in goats following simulated submarine escape: 1993-2006.

    Science.gov (United States)

    Seddon, F M; Thacker, J C; Fisher, A S; Jurd, K M; White, M G; Loveman, G A M

    2014-01-01

    The United Kingdom Ministry of Defence commissioned work to define the relationship between the internal pressure of a distressed submarine (DISSUB), the depth from which escape is made and the risk of decompression illness (DCI). The program of work used an animal model (goat) to define these risks and this paper reports the incidence and type of DCI observed. A total of 748 pressure exposures comprising saturation only, escape only or saturation followed by escape were conducted in the submarine escape simulator between 1993 and 2006. The DCI following saturation exposures was predominantly limb pain, whereas following escape exposures the DCI predominantly involved the central nervous system and was fast in onset. There was no strong relationship between the risk of DCI and the range of escape depths investigated. The risk of DCI incurred from escape following saturation was greater than that obtained by combining the risks for the independent saturation only, and escape only, exposures. The output from this program of work has led to improved advice on the safety of submarine escape.

  5. On the relative contributions of noncontingent reinforcement and escape extinction in the treatment of food refusal.

    Science.gov (United States)

    Reed, Gregory K; Piazza, Cathleen C; Patel, Meeta R; Layer, Stacy A; Bachmeyer, Melanie H; Bethke, Stephanie D; Gutshall, Katharine A

    2004-01-01

    In the current investigation, we evaluated the relative effects of noncontingent reinforcement (NCR), escape extinction, and a combination of NCR and escape extinction as treatment for the feeding problems exhibited by 4 children. For each participant, consumption increased only when escape extinction was implemented, independent of whether NCR was present or absent. These results were consistent with prior research suggesting that positive reinforcement alone is insufficient for increasing consumption, and that escape extinction often is necessary to increase and maintain food acceptance. However, NCR appeared to decrease inappropriate behavior for some participants.

  6. Escape and avoidance learning in the earthworm Eisenia hortensis

    Directory of Open Access Journals (Sweden)

    W. Jeffrey Wilson

    2014-01-01

    Full Text Available Interest in instrumental learning in earthworms dates back to 1912 when Yerkes concluded that they can learn a spatial discrimination in a T-maze. Rosenkoetter and Boice determined in the 1970s that the “learning” that Yerkes observed was probably chemotaxis and not learning at all. We examined a different form of instrumental learning: the ability to learn both to escape and to avoid an aversive stimulus. Freely moving “master” worms could turn off an aversive white light by increasing their movement; the behavior of yoked controls had no effect on the light. We demonstrate that in as few as 12 trials the behavior of the master worms comes under the control of this contingency.

  7. Novel Anti-Melanoma Immunotherapies: Disarming Tumor Escape Mechanisms

    Directory of Open Access Journals (Sweden)

    Sivan Sapoznik

    2012-01-01

    Full Text Available The immune system fights cancer and sometimes temporarily eliminates it or reaches an equilibrium stage of tumor growth. However, continuous immunological pressure also selects poorly immunogenic tumor variants that eventually escape the immune control system. Here, we focus on metastatic melanoma, a highly immunogenic tumor, and on anti-melanoma immunotherapies, which recently, especially following the FDA approval of Ipilimumab, gained interest from drug development companies. We describe new immunomodulatory approaches currently in the development pipeline, focus on the novel CEACAM1 immune checkpoint, and compare its potential to the extensively described targets, CTLA4 and PD1. This paper combines multi-disciplinary approaches and describes anti-melanoma immunotherapies from molecular, medical, and business angles.

  8. The great escape: viral strategies to counter BST-2/tetherin.

    Directory of Open Access Journals (Sweden)

    Janet L Douglas

    2010-05-01

    Full Text Available The interferon-induced BST-2 protein has the unique ability to restrict the egress of HIV-1, Kaposi's sarcoma-associated herpesvirus (KSHV, Ebola virus, and other enveloped viruses. The observation that virions remain attached to the surface of BST-2-expressing cells led to the renaming of BST-2 as "tetherin". However, viral proteins such as HIV-1 Vpu, simian immunodeficiency virus Nef, and KSHV K5 counteract BST-2, thereby allowing mature virions to readily escape from infected cells. Since the anti-viral function of BST-2 was discovered, there has been an explosion of research into several aspects of this intriguing interplay between host and virus. This review focuses on recent work addressing the molecular mechanisms involved in BST-2 restriction of viral egress and the species-specific countermeasures employed by various viruses.

  9. Will 3552 Don Quixote escape from the Solar System?

    Directory of Open Access Journals (Sweden)

    Suryadi Siregar

    2011-05-01

    Full Text Available Asteroid 1983 SA, well known as 3552 Don Quixote, is one of Near Earth Asteroids (NEAs which is the most probable candidate for the cometary origin, or otherwise as Jupiter-Family-Comets (JFCs. The aim of this study is to investigate the possibility of 3552 Don Quixote to be ejected from the Solar System. This paper presents an orbital evolution of 100 hypothetical asteroids generated by cloning 3552 Don Quixote. Investigation of its orbital evolution is conducted by using the SWIFT subroutine package, where the gravitational perturbations of eight major planets in the Solar System are considered. Over very short time scales (220 kyr relative to the Solar System life time (10 Gyr, the asteroid 3552 Don Quixote gave an example of chaotic motion that can cause asteroid to move outward and may be followed by escaping from the Solar System. Probability of ejection within the 220 kyr time scale is 50%.

  10. Initiating a watch list for Ebola virus antibody escape mutations

    Directory of Open Access Journals (Sweden)

    Craig R. Miller

    2016-02-01

    Full Text Available The 2014 Ebola virus (EBOV outbreak in West Africa is the largest in recorded history and resulted in over 11,000 deaths. It is essential that strategies for treatment and containment be developed to avoid future epidemics of this magnitude. With the development of vaccines and antibody-based therapies using the envelope glycoprotein (GP of the 1976 Mayinga strain, one important strategy is to anticipate how the evolution of EBOV might compromise these efforts. In this study we have initiated a watch list of potential antibody escape mutations of EBOV by modeling interactions between GP and the antibody KZ52. The watch list was generated using molecular modeling to estimate stability changes due to mutation. Every possible mutation of GP was considered and the list was generated from those that are predicted to disrupt GP-KZ52 binding but not to disrupt the ability of GP to fold and to form trimers. The resulting watch list contains 34 mutations (one of which has already been seen in humans at six sites in the GP2 subunit. Should mutations from the watch list appear and spread during an epidemic, it warrants attention as these mutations may reflect an evolutionary response from the virus that could reduce the effectiveness of interventions such as vaccination. However, this watch list is incomplete and emphasizes the need for more experimental structures of EBOV interacting with antibodies in order to expand the watch list to other epitopes. We hope that this work provokes experimental research on evolutionary escape in both Ebola and other viral pathogens.

  11. Initiating a watch list for Ebola virus antibody escape mutations.

    Science.gov (United States)

    Miller, Craig R; Johnson, Erin L; Burke, Aran Z; Martin, Kyle P; Miura, Tanya A; Wichman, Holly A; Brown, Celeste J; Ytreberg, F Marty

    2016-01-01

    The 2014 Ebola virus (EBOV) outbreak in West Africa is the largest in recorded history and resulted in over 11,000 deaths. It is essential that strategies for treatment and containment be developed to avoid future epidemics of this magnitude. With the development of vaccines and antibody-based therapies using the envelope glycoprotein (GP) of the 1976 Mayinga strain, one important strategy is to anticipate how the evolution of EBOV might compromise these efforts. In this study we have initiated a watch list of potential antibody escape mutations of EBOV by modeling interactions between GP and the antibody KZ52. The watch list was generated using molecular modeling to estimate stability changes due to mutation. Every possible mutation of GP was considered and the list was generated from those that are predicted to disrupt GP-KZ52 binding but not to disrupt the ability of GP to fold and to form trimers. The resulting watch list contains 34 mutations (one of which has already been seen in humans) at six sites in the GP2 subunit. Should mutations from the watch list appear and spread during an epidemic, it warrants attention as these mutations may reflect an evolutionary response from the virus that could reduce the effectiveness of interventions such as vaccination. However, this watch list is incomplete and emphasizes the need for more experimental structures of EBOV interacting with antibodies in order to expand the watch list to other epitopes. We hope that this work provokes experimental research on evolutionary escape in both Ebola and other viral pathogens.

  12. Suppressive effects of Lactobacillus casei cells, a bacterial immunostimulant, on the incidence of spontaneous thymic lymphoma in AKR mice.

    Science.gov (United States)

    Watanabe, T

    1996-06-01

    The mean survival age of female AKR/J mice was significantly prolonged, the enlargement of thymus was markedly suppressed, and the proliferation of ecotropic and recombinant murine leukemia viruses (MuLV) was markedly inhibited when 8-week-old female AKR/J mice were injected intraperitoneally (i.p.) with heat-killed Lactobacillus casei cells twice weekly for 8 weeks. In contrast, such actions of heat-killed L. casei cells were not seen in 20-week-old female AKR/J mice. The leukemogenic activity of the cell-free extract of thymus from adult female AKR/J mice in newborn female AKR/J mice was drastically reduced by i.p. treatment with heat-killed L. casei cells. The difference in adjuvant effectiveness of heat-killed L. casei cells on 8- and 20-week-old animals may be dependent on the difference in the enhancing activity of the cell-mediated immune systems between the groups induced by heat-killed L. casei cells, and, as a result, on the difference in the degree of proliferation of ecotropic and recombinant MuLV in thymus, which consequently causes thymic lymphoma.

  13. Sequential mutations in Notch1, Fbxw7, and Tp53 in radiation-induced mouse thymic lymphomas.

    Science.gov (United States)

    Jen, Kuang-Yu; Song, Ihn Young; Banta, Karl Luke; Wu, Di; Mao, Jian-Hua; Balmain, Allan

    2012-01-19

    T-cell acute lymphoblastic lymphomas commonly demonstrate activating Notch1 mutations as well as mutations or deletions in Fbxw7. However, because Fbxw7 targets Notch1 for degradation, genetic alterations in these genes are expected to be mutually exclusive events in lymphomagenesis. Previously, by using a radiation-induced Tp53-deficient mouse model for T-cell acute lymphoblastic lymphoma, we reported that loss of heterozygosity at the Fbxw7 locus occurs frequently in a Tp53-dependent manner. In the current study, we show that these thymic lymphomas also commonly exhibit activating Notch1 mutations in the proline-glutamic acid-serine-threonine (PEST) domain. Moreover, concurrent activating Notch1 PEST domain mutations and single-copy deletions at the Fbxw7 locus occur with high frequency in the same individual tumors, indicating that these changes are not mutually exclusive events. We further demonstrate that although Notch1 PEST domain mutations are independent of Tp53 status, they are completely abolished in mice with germline Fbxw7 haploinsufficiency. Therefore, Notch1 PEST domain mutations only occur when Fbxw7 expression levels are intact. These data suggest a temporal sequence of mutational events involving these important cancer-related genes, with Notch1 PEST domain mutations occurring first, followed by Fbxw7 deletion, and eventually by complete loss of Tp53.

  14. Medullary Thymic Epithelial Cells and Central Tolerance in Autoimmune Hepatitis Development: Novel Perspective from a New Mouse Model

    Directory of Open Access Journals (Sweden)

    Konstantina Alexandropoulos

    2015-01-01

    Full Text Available Autoimmune hepatitis (AIH is an immune-mediated disorder that affects the liver parenchyma. Diagnosis usually occurs at the later stages of the disease, complicating efforts towards understanding the causes of disease development. While animal models are useful for studying the etiology of autoimmune disorders, most of the existing animal models of AIH do not recapitulate the chronic course of the human condition. In addition, approaches to mimic AIH-associated liver inflammation have instead led to liver tolerance, consistent with the high tolerogenic capacity of the liver. Recently, we described a new mouse model that exhibited spontaneous and chronic liver inflammation that recapitulated the known histopathological and immunological parameters of AIH. The approach involved liver-extrinsic genetic engineering that interfered with the induction of T-cell tolerance in the thymus, the very process thought to inhibit AIH induction by liver-specific expression of exogenous antigens. The mutation led to depletion of specialized thymic epithelial cells that present self-antigens and eliminate autoreactive T-cells before they exit the thymus. Based on our findings, which are summarized below, we believe that this mouse model represents a relevant experimental tool towards elucidating the cellular and molecular aspects of AIH development and developing novel therapeutic strategies for treating this disease.

  15. European SpaceCraft for the study of Atmospheric Particle Escape (ESCAPE): a mission proposed in response to the ESA M5-call

    Science.gov (United States)

    Dandouras, Iannis; Yamauchi, Masatoshi; Rème, Henri; De Keyser, Johan; Marghitu, Octav; Fazakerley, Andrew; Grison, Benjamin; Kistler, Lynn; Milillo, Anna; Nakamura, Rumi; Paschalidis, Nikolaos; Paschalis, Antonis; Pinçon, Jean-Louis; Sakanoi, Takeshi; Wieser, Martin; Wurz, Peter; Yoshikawa, Ichiro; Häggström, Ingemar; Liemohn, Mike; Tian, Feng

    2017-04-01

    ESCAPE is a mission proposed in response to the ESA-M5 call that will quantitatively estimate the amount of escaping particles of the major atmospheric components (nitrogen and oxygen), as neutral and ionised species, escaping from the Earth as a magnetised planet. The spatial distribution and temporal variability of the flux of these species and their isotopic composition will be for the first time systematically investigated in an extended altitude range, from the exobase/upper ionosphere (500 km altitude) up to the magnetosphere. The goal is to understand the importance of each escape mechanism, its dependence on solar and geomagnetic activity, and to infer the history of the Earth's atmosphere over a long (geological scale) time period. Since the solar EUV and solar wind conditions during solar maximum at present are comparable to the solar minimum conditions 1-2 billion years ago, the escaping amount and the isotope and N/O ratios should be obtained as a function of external forcing (solar and geomagnetic conditions) to allow a scaling to the past. The result will be used as a reference to understand the atmospheric/ionospheric evolution of magnetised planets. To achieve this goal, a slowly spinning spacecraft is proposed equipped with a suite of instruments developed and supplied by an international consortium. These instruments will detect the upper atmosphere and magnetosphere escaping populations by a combination of in-situ measurements and of remote-sensing observations.

  16. Escapement of Cape hakes under the fishing line of the Namibian ...

    African Journals Online (AJOL)

    The objective of this study was to establish whether Cape hakes Merluccius capensis and M. paradoxus escape under the fishing line and to identify any species or length dependence of escape rates. Experiments were carried out in Namibian waters during two cruises in October 2002 and October 2003. A collection bag ...

  17. The rate of immune escape vanishes when multiple immune responses control an HIV infection

    NARCIS (Netherlands)

    van Deutekom, Hanneke W. M.; Wijnker, Gilles; de Boer, Rob J.

    2013-01-01

    During the first months of HIV infection, the virus typically evolves several immune escape mutations. These mutations are found in epitopes in viral proteins and reduce the impact of the CD8⁺ T cells specific for these epitopes. Recent data show that only a subset of the epitopes escapes, that most

  18. Behavioral analyses of wind-evoked escape of the cricket, Gryllodes sigillatus.

    Science.gov (United States)

    Kanou, Masamichi; Konishi, Atsuko; Suenaga, Rie

    2006-04-01

    The wind-evoked escape behavior of the cricket Gryllodes sigillatus was investigated using an air puff stimulus. A high velocity air puff elicited the escape behavior in many crickets. The crickets tended to escape away from the stimulus source, but the direction was not accurately oriented 180 degrees from the stimulus. After bilateral cercal ablation, only a few crickets showed wind-evoked escape behavior, and their response rates did not increase even 19 days after ablation. Therefore, information on air motion detected by cercal filiform hairs is essential for triggering wind-evoked behavior. After unilateral cercal ablation, the 81.3% response rate of intact crickets decreased to 16.5%, that is, it decreased to almost 20% that of intact crickets. One week after unilateral cercal ablation, the response rate recovered to more than 60% that of intact crickets. However, the accuracy rate of the escape direction of G. sigillatus showed no change even immediately after the unilateral cercal ablation. Therefore, both cerci are not necessarily required to determine the escape direction. The behavioral characteristics of wind-evoked escape of G. sigillatus are compared with those of another species of cricket, Gryllus bimaculatus. The two species of cricket employ different strategies for wind-evoked escape.

  19. A Substantial Plume of Escaping Planetary Ions in the MSE Northern Hemisphere Observed by MAVEN

    Science.gov (United States)

    Dong, Y.; Fang, X.; Brain, D. A.; McFadden, J. P.; Halekas, J. S.; Connerney, J. E. P.; Curry, S.; Harada, Y.; Luhmann, J. G.; Jakosky, B. M.

    2015-12-01

    The Mars-solar wind interaction accelerates and transports planetary ions away from Mars through a number of processes, including pick-up by the electromagnetic fields. The Mars Atmospheric and Volatile EvolutioN (MAVEN) spacecraft has frequently detected strong escaping planetary ion fluxes in both tailward and upstream solar wind motional electric field directions since the beginning of its science phase in November 2014. Our statistical study using three-month MAVEN data from November 2014 through February 2015 illustrates a substantial plume-like escaping planetary ion population organized by the upstream electric field with strong fluxes widely distributed in the northern hemisphere of the Mars-Sun-Electric-field (MSE) coordinate system, which is generally consistent with model predictions. The plume constitutes an important planetary ion escape channel from the Martian atmosphere in addition to the tailward escape. The >25eV O+ escape rate through the plume is estimated to be ~35% of the tailward escape and ~25% of the total escape. We will compare the dynamics of the plume and tailward escaping ions based on their velocity-space distributions with respect to the electromagnetic fields. We will also discuss the variations of the plume characteristics between different ion species (O+, O2+, and CO2+) and from the effect of different solar wind and interplanetary magnetic field (IMF) conditions.

  20. Escaping blood-fed malaria mosquitoes minimize tactile detection without compromising on take-off speed

    NARCIS (Netherlands)

    Muijres, F.T.; Chang, S.W.; Veen, van W.G.; Spitzen, J.; Biemans, B.T.; Koehl, M.A.R.; Dudley, R.

    2017-01-01

    To escape after taking a blood meal, a mosquito must exert forces sufficiently high to take off when carrying a load roughly equal to its body weight, while simultaneously avoiding detection by minimizing tactile signals exerted on the host’s skin. We studied this trade-off between escape speed and

  1. Computer Self-Efficacy, Competitive Anxiety and Flow State: Escaping from Firing Online Game

    Science.gov (United States)

    Hong, Jon-Chao; Pei-Yu, Chiu; Shih, Hsiao-Feng; Lin, Pei-Shin; Hong, Jon-Chao

    2012-01-01

    Flow state in game playing affected by computer self-efficacy and game competitive anxiety was studied. In order to examine the effect of those constructs with high competition, this study select "Escaping from firing online game" which require college students to escape from fire and rescue people and eliminate the fire damage along the way of…

  2. Treatment of Escape-Maintained Behavior with Positive Reinforcement: The Role of Reinforcement Contingency and Density

    Science.gov (United States)

    Ingvarsson, Einar T.; Hanley, Gregory P.; Welter, Katherine M.

    2009-01-01

    Functional analyses suggested that the disruptive behavior of three preschool children was maintained by escape from demands. While keeping the escape contingency intact, we conducted (a) a density analysis in which the children earned preferred items for task completion according to two schedules that varied in reinforcement density, and (b) a…

  3. Plasma Clouds and Snowplows: Bulk Plasma Escape from Mars Observed by MAVEN

    Science.gov (United States)

    Halekas, J. S.; Brain, D. A.; Ruhunusiri, S.; McFadden, J. P.; Mitchell, D. L.; Mazelle, C.; Connerney, J. E. P.; Harada, Y.; Hara, T.; Espley, J. R.; hide

    2016-01-01

    We present initial Mars Atmosphere and Volatile EvolutioN (MAVEN) observations and preliminary interpretation of bulk plasma loss from Mars. MAVEN particle and field measurements show that planetary heavy ions derived from the Martian atmosphere can escape in the form of discrete coherent structures or "clouds." The ions in these clouds are unmagnetized or weakly magnetized, have velocities well above the escape speed, and lie directly downstream from magnetic field amplifications, suggesting a "snowplow" effect. This postulated escape process, similar to that successfully used to explain the dynamics of active gas releases in the solar wind and terrestrial magnetosheath, relies on momentum transfer from the shocked solar wind protons to the planetary heavy ions, with the electrons and magnetic field acting as intermediaries. Fluxes of planetary ions on the order of 10(exp 7)/sq cm/s can escape by this process, and if it operates regularly, it could contribute 10-20% of the current ion escape from Mars.

  4. Antarctic krill; assessment of mesh size selectivity and escape mortality from trawls

    DEFF Research Database (Denmark)

    Krafft, Bjørn A.; Krag, Ludvig Ahm; Herrmann, Bent

    2015-01-01

    Marine AS. The project will examine krill escape mortality from the codend during a full scale field experiment, model size selectivity and escape mortality in codends including different designs and assess the size selectivity in the trawl body forward of the codend. Based on end results from the preceding...... examinations we will be able to predict size selectivity and escape mortality from the entire trawl body with the appurtenant mortality for different trawl designs......This working paper presents the aims and methodology for a three-year-project (commenced in 2015) assessing size selectivity and escape mortality of Antarctic krill from trawl nets. The project is widely based on acquired experiences from a completed study Net Escapement of Antarctic krill...

  5. Highlights of the Global HIV-1 CSF Escape Consortium Meeting, 9 June 2016, Bethesda, MD, USA.

    Science.gov (United States)

    Joseph, Jeymohan; Cinque, Paola; Colosi, Deborah; Dravid, Ameet; Ene, Luminita; Fox, Howard; Gabuzda, Dana; Gisslen, Magnus; Beth Joseph, Sarah; Letendre, Scott; Mukerji, Shibani S; Nath, Avindra; Perez-Valero, Ignacio; Persaud, Deborah; Price, Richard W; Rao, Vasudev R; Sacktor, Ned; Swanstrom, Ronald; Winston, Alan; Wojna, Valerie; Wright, Edwina; Spudich, Serena

    2016-10-05

    CSF HIV escape is a recently recognised phenomenon that suggests that despite suppressive treatment, HIV RNA may be detected in the CNS compartment in some individuals. In rare cases this is associated with clinical neurological disease, while in most cases, neurological consequences are not apparent. Attempts at characterising the biological substrates of CSF escape and further investigating the neurological consequences need to be made to better understand the implications of this condition for the HIV cure agenda as well as for clinical outcomes. The Global CSF HIV-1 Escape Consortium meeting, convened by the US National Institute of Mental Health, was a first step to gather investigators from diverse sites to discuss opportunities for future collaborative work on this emerging issue. To better understand CSF HIV escape and allow cross-site data reconciliation, it will be useful to reach a consensus set of definitions of the distinct forms of CSF escape, without which concerted cross-site efforts are difficult.

  6. Improving the effectiveness of escape windows in directed Norway lobster Nephrops norvegicus trawl fisheries

    DEFF Research Database (Denmark)

    Madsen, Niels; Holst, René; Frandsen, Rikke

    2012-01-01

    A substantial improvement in the bycatch selectivity of Norway lobster Nephrops norvegicus trawls is required, particularly with respect to cod Gadus morhua , whose stocks are at low levels in several areas. Conventional escape windows are not adequate to properly release cod and other bycatch...... species caught in the trawls. To address this issue, we developed a novel sorting box concept consisting of a four-panel section with a window on the top in order to improve the escape of cod and other bycatch species through an escape window while retaining the target catch of Norway lobster. The concept....... The reduction in bycatch decreased with decreasing mesh size and increasing height of the sorting box. Escape of Norway lobster through the escape window was limited. A modified version of the sorting box concept was implemented in the Kattegat fishery from 2009 onwards...

  7. Mass fractionation during transonic escape and implications for loss of water from Mars and Venus

    International Nuclear Information System (INIS)

    Zahnle, K.J.; Kasting, J.F.

    1986-01-01

    Hydrodynamic escape of hydrogen from a planetary atmosphere can remove heavier gases as well as hydrogen, provided that the escape rate is sufficiently large. Analytic approximations for the degree of mass fractionation of a trace species during hydrodynamic escape are compared with accurate numerical solutions for the case of transonic outflow. The analytic approximations are most accurate when the ratio of molecular weights of the heavier and lighter constituents is large so that nonlinear terms in the momentum equation for the heavy constituent become small. The simplest analytic formula is readily generalized to the case where a heavy constituent is also a major species. Application of the generalized formula to hypothetical episodes of hydrodynamic escape from Venus and Mars suggests that both hydrogen and oxygen could have escaped; thus, substantial quantities of water may have been lost without the need to oxidize large amounts of the crust. 29 references

  8. Escape peak ratios in silicon X-ray charge coupled devices (CCDs)

    International Nuclear Information System (INIS)

    McCarthy, K.J.; Owens, A.; Keay, A.

    1997-01-01

    The intensity of the escape peak from the CCDs developed for the Joint European X-ray Telescope (JET-X) has been investigated over the energy range 2-10 keV. Both measured and calculated escape peak ratios (i.e., the ratio of counts in the escape peak to the sum of the counts in the escape and main peaks) are found to be in excellent agreement for all event sizes (i.e., single pixel events, 1 and 2 pixel events, etc.). Using a Monte Carlo simulation the escape peak ratio has been investigated as a function of pixel size and depletion depth. For completeness, we list the energy dependent parameterised forms for five CCDs used in three major astronomy missions. (orig.)

  9. The return of international labour migrants in the ESCAP Region.

    Science.gov (United States)

    1986-03-01

    The social phenomenon of massive temporary international labor migration from the ESCAP region has emerged extremely rapidly. Within 10 years, the number of persons from ESCAP countries grew from a negligible one to 3.5 million. Related research and government policies have lagged behind this latest surge in migration. Most research conducted has been small-scale and lacks an analytical or theoretical framework. Policy formulation for temporary labor migration is difficult because most of the rapid growth in the industry has occurred as a result of private efforts, with a minimum of government intervention. It is now difficult, for the government to provide effective regulations or measures to stimulate and assist the process. Regulations on compulsory remittances or overseas minimum wages have proved to be unrealistic and, if not rescinded, are routinely circumvented. The most effective policies to assist return migrants may not be those which are intended to do so, but those which control the earlier stages of the migration process, such as recruitment, working conditions, and banking arrangements. The most valuable policies may also include those affecting education, training, employment, and general socioeconomic growth. Governments are recommended to provide social services for migrants and their families who are experiencing problems, and to institute community programs in areas with a large number of labor migrants. Governmental efforts to promote forms of labor migration beneficial to the workers would be valuable and should include measures to identify overseas labor markets for employing its nationals, government ot government labor contracts, and government participation in joint-venture projects. International migration should be analyzed in the context of theories and social change in order for governments to formulate effective measures for the reintegration of returning workers. Labor migration on the current scale has many social implications for

  10. Effects of metamorphosis on the aquatic escape response of the two-lined salamander (Eurycea bislineata).

    Science.gov (United States)

    Azizi, Emanuel; Landberg, Tobias

    2002-03-01

    Although numerous studies have described the escape kinematics of fishes, little is known about the aquatic escape responses of salamanders. We compare the escape kinematics of larval and adult Eurycea bislineata, the two-lined salamander, to examine the effects of metamorphosis on aquatic escape performance. We hypothesize that shape changes associated with resorption of the larval tail fin at metamorphosis will affect aquatic locomotor performance. Escape responses were recorded using high-speed video, and the effects of life stage and total length on escape kinematics were analyzed statistically using analysis of covariance. Our results show that both larval and adult E. bislineata use a two-stage escape response (similar to the C-starts of fishes) that consists of a preparatory (stage 1) and a propulsive (stage 2) stroke. The duration of both kinematic stages and the distance traveled during stage 2 increased with total length. Both larval and adult E. bislineata had final escape trajectories that were directed away from the stimulus. The main kinematic difference between larvae and adults is that adults exhibit significantly greater maximum curvature during stage 1. Total escape duration and the distance traveled during stage 2 did not differ significantly between larvae and adults. Despite the significantly lower tail aspect ratio of adults, we found no significant decrease in the overall escape performance of adult E. bislineata. Our results suggest that adults may compensate for the decrease in tail aspect ratio by increasing their maximum curvature. These findings do not support the hypothesis that larvae exhibit better locomotor performance than adults as a result of stronger selective pressures on early life stages.

  11. Evolutionary invasion and escape in the presence of deleterious mutations.

    Directory of Open Access Journals (Sweden)

    Claude Loverdo

    Full Text Available Replicators such as parasites invading a new host species, species invading a new ecological niche, or cancer cells invading a new tissue often must mutate to adapt to a new environment. It is often argued that a higher mutation rate will favor evolutionary invasion and escape from extinction. However, most mutations are deleterious, and even lethal. We study the probability that the lineage will survive and invade successfully as a function of the mutation rate when both the initial strain and an adaptive mutant strain are threatened by lethal mutations. We show that mutations are beneficial, i.e. a non-zero mutation rate increases survival compared to the limit of no mutations, if in the no-mutation limit the survival probability of the initial strain is smaller than the average survival probability of the strains which are one mutation away. The mutation rate that maximizes survival depends on the characteristics of both the initial strain and the adaptive mutant, but if one strain is closer to the threshold governing survival then its properties will have greater influence. These conclusions are robust for more realistic or mechanistic depictions of the fitness landscapes such as a more detailed viral life history, or non-lethal deleterious mutations.

  12. Human embryo immune escape mechanisms rediscovered by the tumor.

    Science.gov (United States)

    Ridolfi, Laura; Petrini, Massimiliano; Fiammenghi, Laura; Riccobon, Angela; Ridolfi, Ruggero

    2009-01-01

    Towards the end of the 1990s, the two opposing theories on immunosurveillance and immunostimulation were extensively studied by researchers in an attempt to understand the complex mechanisms that regulate the relation between tumors and the host's immune system. Both theories probably have elements that would help us to comprehend how the host can induce anti-tumor clinical responses through stimulation of the immune system and which could also give us a deeper insight into the mechanisms of tumor immunosuppression. The model that most resembles the behavior of tumor cells in terms of growth, infiltration and suppression of the immune system of the environment in which they live is undoubtedly that of the embryonic cell. The fetus behaves like an allogenic transplant within the mother's body, using every means it has to escape from and defend itself against the mother's immune system. The majority of these mechanisms are the same as those found in tumor cells: antigenic loss, lack of expression of classic HLA-I molecules, production of immunosuppressive cytokines, induction of lack of expression of co-stimulatory molecules in antigen presenting cells, and induction of apoptosis in infiltrating lymphocytes, with activation of a type Th2 regulatory lymphocyte response. A careful and comparative study of key mechanisms capable of triggering tolerance or cytotoxicity in both embryonic and tumor cells could prove immensely valuable in designing new strategies for anti-tumor immunotherapy.

  13. Intertextuality in Novel: An Escape from Patriarchal Soliloquy

    Directory of Open Access Journals (Sweden)

    Nargess Bagheri

    2015-12-01

    Full Text Available Hypertextuality is one of the intertextual relationships introduced by Gerard Genette. According to him, hypertextuality includes all the relationships which the hypertext has with the previous text, i.e. the hypotext. However, he does not consider the relationship between these two texts to be in such a way that the hypertext is the interpretation of the hypotext. On the other hand, other theorizers including Bakhtin, regard the conversation between texts a way to escape a one-voiced and dominant discourse. From this viewpoint, the intertextual relationships of Sadegh Hedayat’s The Blind Owl, with Shahrnoush Parsipour’s The Blue Mind and Abbas Maroufi’s The Body of Farhad are in such a way that The Blind Owl can be regarded as a hypotext for the other 2 novels but these two novels interpret the text differently. The present study aims to examine the intertextual relationships between these 3 novels and explore how a multiple-voiced conversation is formed between them.

  14. Thermal and quantum escape of fractional Josephson vortices

    Energy Technology Data Exchange (ETDEWEB)

    Poehler, Hanna; Kienzle, Uta; Buckenmaier, Kai; Gaber, Tobias; Koelle, Dieter; Kleiner, Reinhold; Goldobin, Edward [Physikalisches Institut, Center for Collective Quantum Phenomena, Universitaet Tuebingen (Germany); Siegel, Michael [Institut fuer Mikro- und Nanoelektronische Systeme, Universitaet Karlsruhe (Germany)

    2009-07-01

    By using a pair of tiny current injectors one can create an arbitrary {kappa} discontinuity of the phase in a long Josephson junction (LJJ) and a fractional Josephson vortex (FJV), carrying a fraction {phi}/{phi}{sub 0}={kappa}/2{pi}{<=}1 of the magnetic flux quantum {phi}{sub 0}{approx}2.07 .10{sup -15} Wb, which is pinned at the discontinuity. If a bias current I, exceeds the critical value I{sub c}({kappa}), an integer fluxon is torn off the discontinuity and the LJJ switches to the voltage state. Due to thermal or quantum fluctuations this escape event may occur at I

  15. EUROGAM: A high efficiency escape suppressed spectrometer array

    Energy Technology Data Exchange (ETDEWEB)

    Nolan, P J [Liverpool Univ. (United Kingdom). Oliver Lodge Lab.

    1992-08-01

    EUROGAM is a UK-France collaboration to develop and build a high efficiency escape suppressed spectrometer array. The project has involved the development of both germanium (Ge) and bismuth germanate (BGO) detectors to produce crystals which are both bigger and have a more complex geometry. As a major investment for the future, the collaboration has developed a new electronics and data acquisition system based on the VXI and VME standards. The array will start its experimental programme in mid 1992 at the Nuclear Structure Facility at Daresbury, U.K. At this stage it will have a total photopeak efficiency (for 1.33 MeV gamma-rays) of {approx} 4.5%. This will give an improvement in sensitivity (relative to presently operating arrays) of a factor of about 10. When EUROGAM moves to France in mid 1993 its photopeak efficiency will have increased to about 8.5% which will result in an increase in sensitivity of a further factor of about 10. In this article I will concentrate on the array which will operate at Daresbury in 1992 and only briefly cover the developments which will take place for the full array before it is used in France in 1993. (author). 13 refs., 2 tabs., 10 figs.

  16. Imaging escape gated MPWC for hard X-ray astronomy

    Energy Technology Data Exchange (ETDEWEB)

    Ubertini, P.; Bazzano, A.; Boccaccini, L.; La Padula, C.; Mastropietro, M.; Patriarca, R.; Polcaro, V.F.; Barbareschi, L.; Perotti, F.; Villa, G.

    1983-11-15

    A scientific forward step in the hard X-ray and soft gamma-ray astronomy will only be possible with the use of a new generation of space borne instruments. Their main characteristics have to be the two-dimensional imaging capability over a large collecting area and the fine spectral resolution in order to discriminate between the weak signal coming from cosmic sources to be detected and the strong background induced by cosmic rays, in the space environment, on the detector. To reach this goal we have developed a new hard X-ray position sensitive proportional counter operating with the escape gate technique in the range 15-150 keV, to be used together with a pseudo-random coded mask in order to obtain sky images. The detector is a high pressure (5 bar) xenon-argon-isobutane filled chamber with a spatial resolution of 30x2 mm and a spectral resolution of 5% at 60 keV on the sensitive area of 3000 cm/sup 2/.

  17. Cellular Adhesion Promotes Prostate Cancer Cells Escape from Dormancy.

    Science.gov (United States)

    Ruppender, Nazanin; Larson, Sandy; Lakely, Bryce; Kollath, Lori; Brown, Lisha; Coleman, Ilsa; Coleman, Roger; Nguyen, Holly; Nelson, Peter S; Corey, Eva; Snyder, Linda A; Vessella, Robert L; Morrissey, Colm; Lam, Hung-Ming

    2015-01-01

    Dissemination of prostate cancer (PCa) cells to the bone marrow is an early event in the disease process. In some patients, disseminated tumor cells (DTC) proliferate to form active metastases after a prolonged period of undetectable disease known as tumor dormancy. Identifying mechanisms of PCa dormancy and reactivation remain a challenge partly due to the lack of in vitro models. Here, we characterized in vitro PCa dormancy-reactivation by inducing cells from three patient-derived xenograft (PDX) lines to proliferate through tumor cell contact with each other and with bone marrow stroma. Proliferating PCa cells demonstrated tumor cell-cell contact and integrin clustering by immunofluorescence. Global gene expression analyses on proliferating cells cultured on bone marrow stroma revealed a downregulation of TGFB2 in all of the three proliferating PCa PDX lines when compared to their non-proliferating counterparts. Furthermore, constitutive activation of myosin light chain kinase (MLCK), a downstream effector of integrin-beta1 and TGF-beta2, in non-proliferating cells promoted cell proliferation. This cell proliferation was associated with an upregulation of CDK6 and a downregulation of E2F4. Taken together, our data provide the first clinically relevant in vitro model to support cellular adhesion and downregulation of TGFB2 as a potential mechanism by which PCa cells may escape from dormancy. Targeting the TGF-beta2-associated mechanism could provide novel opportunities to prevent lethal PCa metastasis.

  18. EUROGAM: A high efficiency escape suppressed spectrometer array

    International Nuclear Information System (INIS)

    Nolan, P.J.

    1992-01-01

    EUROGAM is a UK-France collaboration to develop and build a high efficiency escape suppressed spectrometer array. The project has involved the development of both germanium (Ge) and bismuth germanate (BGO) detectors to produce crystals which are both bigger and have a more complex geometry. As a major investment for the future, the collaboration has developed a new electronics and data acquisition system based on the VXI and VME standards. The array will start its experimental programme in mid 1992 at the Nuclear Structure Facility at Daresbury, U.K. At this stage it will have a total photopeak efficiency (for 1.33 MeV gamma-rays) of ∼ 4.5%. This will give an improvement in sensitivity (relative to presently operating arrays) of a factor of about 10. When EUROGAM moves to France in mid 1993 its photopeak efficiency will have increased to about 8.5% which will result in an increase in sensitivity of a further factor of about 10. In this article I will concentrate on the array which will operate at Daresbury in 1992 and only briefly cover the developments which will take place for the full array before it is used in France in 1993. (author). 13 refs., 2 tabs., 10 figs

  19. Controlling ventilation for safe escape from coal mine fires

    Energy Technology Data Exchange (ETDEWEB)

    Wala, A M [University of Kentucky, Lexington, KY (United States). Mining Engineering Dept.

    1966-04-01

    If a fire occurs outby an underground coal mine section, the immediate safe evacuation of miners from the working section should always take precedence. Unfortunately, in many cases, the dedicated escapeway (escape routes) for the evacuation of the miners become contaminated by the byproducts of fire from the adjacent entries. The purpose of this paper is to present the ventilation-control process that would keep the escapeway free from contaminants and, thus, available for travel. A few scenarios of mine fires in longwall development panels are analysed and discussed. To perform these studies, a mine-fire simulator (MFS) was used. This (MFS) provides a dynamic representation of the fire`s progress (in real time) and gives a color-graphic visualization of the spready of oxygen, combustion products and temperature of the gases throughout the ventilation system. Also presented and discussed are ways in which the MFS can be used as a training and teaching tool for miners and particularly, for ventilation and safety specialists. 7 refs., 10 figs.

  20. ESCAPE. Energy Security and ClimAte Policy Evaluation

    International Nuclear Information System (INIS)

    Kessels, J.R.; Bakker, S.J.A.

    2005-05-01

    Climate change and energy supply security policy are currently not integrated in most countries, despite possible synergies. The ESCAPE approach suggests that linking climate change policy with security of energy supply could improve climate change policy at both a national and international level. The report explores the interaction between policies of energy security and climate change and the options of inclusion of energy security issues into national and international post-2012 climate negotiations. It emphasises the importance of the US in this regard and takes a close look at US energy policy documents. It appears that current US energy policy is not directed towards reducing its reliance on imported fossil fuel, even though the government has a strong preference for this. This study shows that measures to reduce import dependency are mostly synergetic with climate policy and gives some options that can be implemented. On an international level, linkages of energy security into post-2012 climate policy may be possible in sectoral bottom-up approaches or technology frameworks. As well, inclusion of a security of supply criterion in international emission trading instruments may provide potential benefits

  1. Diethylstilbestrol alters positive and negative selection of T cells in the thymus and modulates T-cell repertoire in the periphery

    International Nuclear Information System (INIS)

    Brown, Nicole; Nagarkatti, Mitzi; Nagarkatti, Prakash S.

    2006-01-01

    Prenatal exposure to diethylstilbestrol (DES) is known to cause altered immune functions and increased susceptibility to autoimmune disease in humans. In the current study, we investigated the effects of DES on T-cell differentiation in the thymus using the HY-TCR transgenic (Tg) mouse model in which the female mice exhibit positive selection of T cells bearing the Tg TCR, while the male mice show negative selection of such T cells. In female HY-TCR-Tg mice, exposure to DES showed more pronounced decrease in thymic cellularity when compared to male mice. Additionally, female mice also showed a significant decrease in the proportion of double-positive (DP) T cells in the thymus and HY-TCR-specific CD8 + T cells in the periphery. Male mice exhibiting negative selection also showed decreased thymic cellularity following DES exposure. Moreover, the male mice showed increased proportion of double-negative (DN) T cells in the thymus and decreased proportion of CD8 + T cells. The density of expression of HY-TCR on CD8 + cells was increased following DES exposure in both females and males. Finally, the proliferative response of thymocytes to mitogens and peripheral lymph node T cells to male H-Y antigen was significantly altered in female and male mice following DES treatment. Taken together, these data suggest that DES alters T-cell differentiation in the thymus by interfering with positive and negative selection processes, which in turn modulates the T-cell repertoire in the periphery

  2. Transient nature of long-term nonprogression and broad virus-specific proliferative T-cell responses with sustained thymic output in HIV-1 controllers.

    Directory of Open Access Journals (Sweden)

    Samantha J Westrop

    Full Text Available HIV-1(+ individuals who, without therapy, conserve cellular anti-HIV-1 responses, present with high, stable CD4(+ T-cell numbers, and control viral replication, facilitate analysis of atypical viro-immunopathology. In the absence of universal definition, immune function in such HIV controllers remains an indication of non-progression.CD4 T-cell responses to a number of HIV-1 proteins and peptide pools were assessed by IFN-gamma ELISpot and lymphoproliferative assays in HIV controllers and chronic progressors. Thymic output was assessed by sjTRECs levels. Follow-up of 41 HIV-1(+ individuals originally identified as "Long-term non-progressors" in 1996 according to clinical criteria, and longitudinal analysis of two HIV controllers over 22 years, was also performed. HIV controllers exhibited substantial IFN-gamma producing and proliferative HIV-1-specific CD4 T-cell responses to both recombinant proteins and peptide pools of Tat, Rev, Nef, Gag and Env, demonstrating functional processing and presentation. Conversely, HIV-specific T-cell responses were limited to IFN-gamma production in chronic progressors. Additionally, thymic output was approximately 19 fold higher in HIV controllers than in age-matched chronic progressors. Follow-up of 41 HIV-1(+ patients identified as LTNP in 1996 revealed the transitory characteristics of this status. IFN-gamma production and proliferative T-cell function also declines in 2 HIV controllers over 22 years.Although increased thymic output and anti-HIV-1 T-cell responses are observed in HIV controllers compared to chronic progressors, the nature of nonprogressor/controller status appears to be transitory.

  3. Regulation of radiation-induced protein kinase Cδ activation in radiation-induced apoptosis differs between radiosensitive and radioresistant mouse thymic lymphoma cell lines

    International Nuclear Information System (INIS)

    Nakajima, Tetsuo; Yukawa, Osami; Tsuji, Hideo; Ohyama, Harumi; Wang, Bing; Tatsumi, Kouichi; Hayata, Isamu; Hama-Inaba, Hiroko

    2006-01-01

    Protein kinase Cδ (PKCδ) has an important role in radiation-induced apoptosis. The expression and function of PKCδ in radiation-induced apoptosis were assessed in a radiation-sensitive mouse thymic lymphoma cell line, 3SBH5, and its radioresistant variant, XR223. Rottlerin, a PKCδ-specific inhibitor, completely abolished radiation-induced apoptosis in 3SBH5. Radiation-induced PKCδ activation correlated with the degradation of PKCδ, indicating that PKCδ activation through degradation is involved in radiation-induced apoptosis in radiosensitive 3SBH5. In radioresistant XR223, radiation-induced PKCδ activation was lower than that in radiosensitive 3SBH5. Cytosol PKCδ levels in 3SBH5 decreased markedly after irradiation, while those in XR223 did not. There was no apparent change after irradiation in the membrane fractions of either cell type. In addition, basal cytosol PKCδ levels in XR223 were higher than those in 3SBH5. These results suggest that the radioresistance in XR223 to radiation-induced apoptosis is due to a difference in the regulation of radiation-induced PKCδ activation compared to that of 3SBH5. On the other hand, Atm -/- mouse thymic lymphoma cells were more radioresistant to radiation-induced apoptosis than wild-type mouse thymic lymphoma cells. Irradiated wild-type cells, but not Atm -/- cells, had decreased PKCδ levels, indicating that the Atm protein is involved in radiation-induced apoptosis through the induction of PKCδ degradation. The decreased Atm protein levels induced by treatment with Atm small interfering RNA had no effect on radiation-induced apoptosis in 3SBH5 cells. These results suggest that the regulation of radiation-induced PKCδ activation, which is distinct from the Atm-mediated cascade, determines radiation sensitivity in radiosensitive 3SBH5 cells

  4. Clonal heterogeneity of thymic B cells from early-onset myasthenia gravis patients with antibodies against the acetylcholine receptor.

    Science.gov (United States)

    Vrolix, Kathleen; Fraussen, Judith; Losen, Mario; Stevens, Jo; Lazaridis, Konstantinos; Molenaar, Peter C; Somers, Veerle; Bracho, Maria Alma; Le Panse, Rozen; Stinissen, Piet; Berrih-Aknin, Sonia; Maessen, Jos G; Van Garsse, Leen; Buurman, Wim A; Tzartos, Socrates J; De Baets, Marc H; Martinez-Martinez, Pilar

    2014-08-01

    Myasthenia gravis (MG) with antibodies against the acetylcholine receptor (AChR-MG) is considered as a prototypic autoimmune disease. The thymus is important in the pathophysiology of the disease since thymus hyperplasia is a characteristic of early-onset AChR-MG and patients often improve after thymectomy. We hypothesized that thymic B cell and antibody repertoires of AChR-MG patients differ intrinsically from those of control individuals. Using immortalization with Epstein-Barr Virus and Toll-like receptor 9 activation, we isolated and characterized monoclonal B cell lines from 5 MG patients and 8 controls. Only 2 of 570 immortalized B cell clones from MG patients produced antibodies against the AChR (both clones were from the same patient), suggesting that AChR-specific B cells are not enriched in the thymus. Surprisingly, many B cell lines from both AChR-MG and control thymus samples displayed reactivity against striated muscle proteins. Striational antibodies were produced by 15% of B cell clones from AChR-MG versus 6% in control thymus. The IgVH gene sequence analysis showed remarkable similarities, concerning VH family gene distribution, mutation frequency and CDR3 composition, between B cells of AChR-MG patients and controls. MG patients showed clear evidence of clonal B cell expansion in contrast to controls. In this latter aspect, MG resembles multiple sclerosis and clinically isolated syndrome, but differs from systemic lupus erythematosus. Our results support an antigen driven immune response in the MG thymus, but the paucity of AChR-specific B cells, in combination with the observed polyclonal expansions suggest a more diverse immune response than expected. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Perioperative Mortality and Long-Term Survival in 80 Dogs and 32 Cats Undergoing Excision of Thymic Epithelial Tumors.

    Science.gov (United States)

    Garneau, Mark S; Price, Lori Lyn; Withrow, Stephen J; Boston, Sarah E; Ewing, Patty J; McClaran, Janet Kovak; Liptak, Julius M; Berg, John

    2015-07-01

    To examine perioperative mortality, long-term survival, causes of death, and prognostic factors for dogs and cats undergoing surgical excision of thymic epithelial tumors (TETs). Multi-institutional case series. Eighty dogs and 32 cats. Follow-up information was obtained for dogs and cats that underwent surgical excision of a TET between 2001 and 2012. Perioperative mortality was 20% in dogs and 22% in cats. No independent risk factors for perioperative mortality were identified. The estimated median survival time for all dogs was 1.69 years (95% CI 0.56-4.32) and the 1- and 4-year survival rates were 55% (95% CI 44-67) and 44% (95% CI 32-56). The estimated median survival time for all cats was 3.71 years (95% CI 0.56-unestimatable) and the 1- and 4-year survival rates were 70% (95% CI 53-87) and 47% (95% CI 0-100). Of animals that survived to discharge, 42% of dogs and 20% of cats eventually died of TET-related causes. The presence of paraneoplastic syndromes (hazard ratio [HR] 5.78, 95% CI 1.64-20.45, P = .007) or incomplete histologic margins (HR 6.09, 95% CI 1.50-24.72, P = .01) were independently associated with decreased survival in dogs. No significant predictors of survival were identified in cats. Conclusions regarding the effect of chemotherapy or radiation therapy could not be made. While there is substantial risk of perioperative death in dogs and cats undergoing surgery for TETs, many animals that survive to discharge have prolonged survival. Survival is significantly decreased in dogs with paraneoplastic syndromes or incomplete histologic margins. © Copyright 2014 by The American College of Veterinary Surgeons.

  6. ΔNp63 controls a TLR3-mediated mechanism that abundantly provides thymic stromal lymphopoietin in atopic dermatitis.

    Directory of Open Access Journals (Sweden)

    Terufumi Kubo

    Full Text Available In the skin lesions of atopic dermatitis (AD, keratinocytes release large quantities of thymic stromal lymphopoietin (TSLP, causing unfavorable inflammation along with skin damage. Nevertheless, how TSLP influences keratinocytes themselves is still unknown. In this study, we showed that ΔNp63, a p53-homologue, predominantly expressed in keratinocytes regulated the receptor complex of TSLP, which determines susceptibility to self-derived TSLP. Expression of TSLP receptors in skin tissues and keratinocytes was assessed by immunohistochemistry and quantitative RT-PCR, and in vitro studies were also performed to examine the functional relevance of ΔNp63 in the expression of TSLP receptors and the constituting autocrine and/or paracrine pathway of TSLP under the condition of stimuli to innate receptors sensing cell damage. The results showed that normal keratinocytes in the upper epidermis preferentially expressed TSLP receptors and conversely lacked ΔNp63, which has an inhibitory effect on the expression of TSLP receptors. Interestingly, the epidermis of AD lesions was found to abundantly contain keratinocytes with low or undetectable levels of ΔNp63 (ΔNp63(lo/-. Moreover, in the absence of ΔNp63, keratinocytes readily presented TSLP and other cytokines by stimuli through Toll-like receptor 3 (TLR3. Together with the evidence that extrinsic TSLP itself augments TSLP production by keratinocytes without ΔNp63, the results indicate that ΔNp63(lo/- keratinocytes generate TSLP through a putative autocrine and/or paracrine pathway upon TLR3 stimulation within AD lesions, since moieties of damaged cells and pathogens stimulate TLR3.

  7. Effects of methylandrostenediol and a lymphostimulatory thymic factor (leucotrofin) on the reactivity of adrenal cortex of X-irradiated A2G mice

    International Nuclear Information System (INIS)

    Abraham, A.D.; Rusu, V.M.; Borsa, M.; Uray, Z.; Banu, C.

    1982-01-01

    Administration of methylandrostenediol alone or with Leucotrofin to whole-body irradiated A2G mice was associated with the diminuation of some enzymatic reactions in the zona fasciculata of the adrenals after 30 days on irradiation in comparison with the irradiated controls. The incorporation rate of (2- 14 C)acetate into free cholesterol and glucocorticoid, de novo synthesized in the adrenals of the protected mice, was decreased compared to the untreated animals. These data showed that late irradiation damage - caused by enhanced synthesis and secretion of catabolic corticosteroids - could be prevented by administration of anabolic steroids and lymphostimulatory thymic factors, which protect the lymphoid system from lymphotoxic agents. (author)

  8. Effects of methylandrostenediol and a lymphostimulatory thymic factor (leucotrofin) on the reactivity of adrenal cortex of X-irradiated A2G mice

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, A.D.; Rusu, V.M.; Borsa, M.; Uray, Z.; Banu, C. (Biological Research Centre, Cluj (Romania))

    1982-03-01

    Administration of methylandrostenediol alone or with Leucotrofin to whole-body irradiated A2G mice was associated with the diminuation of some enzymatic reactions in the zona fasciculata of the adrenals after 30 days on irradiation in comparison with the irradiated controls. The incorporation rate of (2-/sup 14/C)acetate into free cholesterol and glucocorticoid, de novo synthesized in the adrenals of the protected mice, was decreased compared to the untreated animals. These data showed that late irradiation damage - caused by enhanced synthesis and secretion of catabolic corticosteroids - could be prevented by administration of anabolic steroids and lymphostimulatory thymic factors, which protect the lymphoid system from lymphotoxic agents.

  9. Means of escape provisions and evacuation simulation of public building in Malaysia and Singapore

    Science.gov (United States)

    Samad, Muna Hanim Abdul; Taib, Nooriati; Ying, Choo Siew

    2017-10-01

    The Uniform Building By-law 1984 of Malaysia is the legal document governing fire safety requirements in buildings. Its prescriptive nature has made the requirements out dated from the viewpoint of current performance based approach in most developed countries. The means of escape provisions is a critical requirement to safeguard occupants' safety in fire especially in public buildings. As stipulated in the UBBL 1984, the means of escape provisions includes sufficient escape routes, travel distance, protection of escape routes, etc. designated as means to allow occupants to escape within a safe period of time. This research aims at investigating the effectiveness of those provisions in public buildings during evacuation process involving massive crowd during emergencies. This research includes a scenario-based study on evacuation processes using two software i.e. PyroSim, a crowd modelling software to conduct smoke study and Pathfinder to stimulate evacuation model of building in Malaysia and Singapore as comparative study. The results show that the buildings used as case study were designed according to Malaysian UBBL 1984 and Singapore Firecode, 2013 respectively provide relative safe means of escape. The simulations of fire and smoke and coupled with simulation of evacuation have demonstrated that although there are adequate exits designated according to fire requirements, the impact of the geometry of atriums on the behavior of fire and smoke have significant effect on escape time especially for unfamiliar user of the premises.

  10. Phenotypical and functional characterization of double-negative (CD4-CD8-) alpha beta T-cell receptor positive cells from an immunodeficient patient

    DEFF Research Database (Denmark)

    Illum, N; Ralfkiaer, E; Pallesen, G

    1991-01-01

    We have characterized CD4-CD8- double-negative (DN) alpha beta TCR+ T cells from a patient with immunodeficiency, lymphocytosis, lymphadenopathy, and hepatosplenomegaly. The majority of peripheral blood lymphocytes were DN alpha beta TCR+ T cells as evaluated by FACS and biochemical analysis...... (MoAbs) indicated a polyclonal T-cell expansion. Thymic biopsy showed normal histology, whereas lymph node biopsy samples showed altered histological and immunohistological patterns with markedly expanded paracortical areas containing the DN T cells of the same phenotype as found in peripheral blood T...

  11. Measuring behaviours for escaping from house fires: use of latent variable models to summarise multiple behaviours.

    Science.gov (United States)

    Ploubidis, G B; Edwards, P; Kendrick, D

    2015-12-15

    This paper reports the development and testing of a construct measuring parental fire safety behaviours for planning escape from a house fire. Latent variable modelling of data on parental-reported fire safety behaviours and plans for escaping from a house fire and multivariable logistic regression to quantify the association between groups defined by the latent variable modelling and parental-report of having a plan for escaping from a house fire. Data comes from 1112 participants in a cluster randomised controlled trial set in children's centres in 4 study centres in the UK. A two class model provided the best fit to the data, combining responses to five fire safety planning behaviours. The first group ('more behaviours for escaping from a house fire') comprised 86% of participants who were most likely to have a torch, be aware of how their smoke alarm sounds, to have external door and window keys accessible, and exits clear. The second group ('fewer behaviours for escaping from a house fire') comprised 14% of participants who were less likely to report these five behaviours. After adjusting for potential confounders, participants allocated to the 'more behaviours for escaping from a house fire group were 2.5 times more likely to report having an escape plan (OR 2.48; 95% CI 1.59-3.86) than those in the "fewer behaviours for escaping from a house fire" group. Multiple fire safety behaviour questions can be combined into a single binary summary measure of fire safety behaviours for escaping from a house fire. Our findings will be useful to future studies wishing to use a single measure of fire safety planning behaviour as measures of outcome or exposure. NCT 01452191. Date of registration 13/10/2011.

  12. Quantifying the impact of human immunodeficiency virus-1 escape from cytotoxic T-lymphocytes.

    Directory of Open Access Journals (Sweden)

    Ulrich D Kadolsky

    2010-11-01

    Full Text Available HIV-1 escape from the cytotoxic T-lymphocyte (CTL response leads to a weakening of viral control and is likely to be detrimental to the patient. To date, the impact of escape on viral load and CD4(+ T cell count has not been quantified, primarily because of sparse longitudinal data and the difficulty of separating cause and effect in cross-sectional studies. We use two independent methods to quantify the impact of HIV-1 escape from CTLs in chronic infection: mathematical modelling of escape and statistical analysis of a cross-sectional cohort. Mathematical modelling revealed a modest increase in log viral load of 0.051 copies ml(-1 per escape event. Analysis of the cross-sectional cohort revealed a significant positive association between viral load and the number of "escape events", after correcting for length of infection and rate of replication. We estimate that a single CTL escape event leads to a viral load increase of 0.11 log copies ml(-1 (95% confidence interval: 0.040-0.18, consistent with the predictions from the mathematical modelling. Overall, the number of escape events could only account for approximately 6% of the viral load variation in the cohort. Our findings indicate that although the loss of the CTL response for a single epitope results in a highly statistically significant increase in viral load, the biological impact is modest. We suggest that this small increase in viral load is explained by the small growth advantage of the variant relative to the wildtype virus. Escape from CTLs had a measurable, but unexpectedly low, impact on viral load in chronic infection.

  13. Escape of the martian protoatmosphere and initial water inventory.

    Science.gov (United States)

    Erkaev, N V; Lammer, H; Elkins-Tanton, L T; Stökl, A; Odert, P; Marcq, E; Dorfi, E A; Kislyakova, K G; Kulikov, Yu N; Leitzinger, M; Güdel, M

    2014-08-01

    Latest research in planet formation indicates that Mars formed within a few million years (Myr) and remained as a planetary embryo that never grew to a more massive planet. It can also be expected from dynamical models that most of Mars' building blocks consisted of material that formed in orbital locations just beyond the ice line which could have contained [Formula: see text] of H 2 O. By using these constraints, we estimate the nebula-captured and catastrophically outgassed volatile contents during the solidification of Mars' magma ocean and apply a hydrodynamic upper atmosphere model for the study of the soft X-ray and extreme ultraviolet (XUV) driven thermal escape of the martian protoatmosphere during the early active epoch of the young Sun. The amount of gas that has been captured from the protoplanetary disk into the planetary atmosphere is calculated by solving the hydrostatic structure equations in the protoplanetary nebula. Depending on nebular properties such as the dust grain depletion factor, planetesimal accretion rates and luminosities, hydrogen envelopes with masses [Formula: see text] to [Formula: see text] could have been captured from the nebula around early Mars. Depending on the before mentioned parameters, due to the planets low gravity and a solar XUV flux that was [Formula: see text] times stronger compared to the present value, our results indicate that early Mars would have lost its nebular captured hydrogen envelope after the nebula gas evaporated, during a fast period of [Formula: see text]. After the solidification of early Mars' magma ocean, catastrophically outgassed volatiles with the amount of [Formula: see text] H 2 O and [Formula: see text] CO 2 could have been lost during [Formula: see text], if the impact related energy flux of large planetesimals and small embryos to the planet's surface lasted long enough, that the steam atmosphere could have been prevented from condensing. If this was not the case, then our results suggest

  14. Escaping 1 MeV tritons in TFTR

    International Nuclear Information System (INIS)

    Zweben, S.J.; Strachan, J.D.; Boivin, R.; Cavallo, A.; Fredrickson, E.D.; McGuire, K.; Mynick, H.E.; White, R.B.

    1989-01-01

    1 MeV tritons created by D-D reactions can simulate the 'single-particle' behavior expected with 3.5 MeV D-T alphas, since the gyroradii and slowing-down of these two particles are similar. This paper describes measurements of the flux of escaping 1 MeV tritons from the TFTR plasma during high power D 0 →D neutral beam injection, and shows that in most cases the observed triton loss is consistent with the classical (single-particle) first-orbit loss model. In this model tritons are lost if their first orbit intersects the wall due to their large banana width, while almost all tritons confined on their first orbit should stay confined until thermalized. The triton detectors are ZnS(Ag) scintillator screens housed in light-tight boxes located just outside the plasma boundary at the bottom of the TFTR vessel. They are particle 'pinhole' cameras which can resolve the triton flux vs. pitch angle (to ±5 o ), energy (to ±50 %), and time (to <20 μsec). The 2-D images of triton flux onto these scintillators are optically coupled to either an intensified TV camera or to photomultiplyer tubes for fast time resolution. The soft x-ray background in an earlier prototype has been eliminated. Although there are presently 8 such detectors in TFTR, this paper discusses results from only the detector located just below the vessel center (R=259 cm, r=102 cm). Note that the '1 MeV triton' signal discussed below also has about a 30 % contribution from 3 MeV protons; however, since these two particles have identical gyroradii they should behave alike. 5 refs., 5 figs

  15. An analytical evaluation for spatial-dependent intra-pebble Dancoff factor and escape probability

    International Nuclear Information System (INIS)

    Kim, Songhyun; Kim, Hong-Chul; Kim, Jong Kyung; Kim, Soon Young; Noh, Jae Man

    2009-01-01

    The analytical evaluation of spatial-dependent intra-pebble Dancoff factors and their escape probabilities is pursued by the model developed in this study. Intra-pebble Dancoff factors and their escape probabilities are calculated as a function of fuel kernel radius, number of fuel kernels, and fuel region radius. The method in this study can be easily utilized to analyze the tendency of spatial-dependent intra-pebble Dancoff factor and spatial-dependent fuel region escape probability for the various geometries because it is faster than the MCNP method as well as good accuracy. (author)

  16. Never ever? Characteristics, outcomes and motivations of patients who abscond or escape: A 5-year review of escapes and absconds from two medium and low secure forensic units.

    Science.gov (United States)

    Mezey, Gillian; Durkin, Catherine; Dodge, Liam; White, Sarah

    2015-12-01

    Absconds and escapes by psychiatric patients from secure forensic psychiatric settings create public anxiety and are poorly understood. To describe secure hospital patients who escape from within the secure perimeter or abscond, and test for differences between these groups. Escapes and absconds between 2008 and 2012 from the medium and low secure forensic psychiatric inpatient units of two London National Health Service Trusts were identified through the Trusts' databases. Demographic, offending, mental health and incident data were extracted from records for each. Seventy-seven incidents, involving 54 patients, were identified over the five years. These were 13 escapes involving 12 patients, representing a rate of 0.04 per 1000 bed days, and 64 absconds involving 42 patients, a rate of 0.26 per 1000 bed days; 15 (28%) patients were absent without leave more than once. Over half of the patients came back voluntarily within 24 hours of leaving. Over 50% of them had drunk alcohol or taken drugs while away from the unit. Escapees were more likely to be transferred prisoners and to have planned their escape, less likely to return to the unit voluntarily and away longer than patients who absconded. Offending was rare during unauthorised leave--just three offences among the 77 incidents; self-harm was more likely. Motives for absconding included: wanting freedom or drink or drugs, family worries and/or dissatisfaction with aspects of treatment. Escapes or absconding from secure healthcare units have different characteristics, but may best be prevented by convergent strategies. Relational security is likely to be as important for foiling plans for the former as it is for reducing boredom, building strong family support and managing substance misuse in the latter. Copyright © 2015 John Wiley & Sons, Ltd.

  17. Trapped as a Group, Escape as a Team: Applying Gamification to Incorporate Team-building Skills Through an ‘Escape Room’ Experience

    Science.gov (United States)

    Lee, Hyunjoo; Rodriguez, Carlos; Rudner, Joshua; Chan, Teresa M; Papanagnou, Dimitrios

    2018-01-01

    Teamwork, a skill critical for quality patient care, is recognized as a core competency by the Accreditation Council for Graduate Medical Education (ACGME). To date, there is no consensus on how to effectively teach these skills in a forum that engages learners, immerses members in life-like activities, and builds both trust and rapport. Recreational ‘Escape Rooms’ have gained popularity in creating a life-like environment that rewards players for working together, solving puzzles, and completing successions of mind-bending tasks in order to effectively ‘escape the room’ in the time allotted. In this regard, escape rooms share many parallels with the multitasking and teamwork that is essential for a successful emergency department (ED) shift. A pilot group of nine emergency medicine (EM) residents and one senior EM faculty member underwent a commercial escape room as part of a team-building exercise in January 2018. The escape room required participants to practice teamwork, communication, task delegation, and critical thinking to tackle waves of increasingly complex puzzles, ranging from hidden objects, physical object assembly (i.e., jigsaw puzzles), and symbol matching. Activities required members to recognize and utilize the collective experiences, skills, knowledge base, and physical abilities of the group. After the game, players underwent a structured ‘game-master’ debriefing facilitated by an employee of the commercial escape room; this was followed by a post-event survey facilitated by a faculty member, which focused on participants’ feelings, experiences, and problem-solving techniques. Escape rooms afford learners the opportunity to engage in an activity that rewards teamwork and effective leadership through experiences that directly link to specific ACGME milestones and educational learning theories. EM participants were engaged in the activity and felt that the escape room reproduced an environment analogous to the ED. The debriefing

  18. Trapped as a Group, Escape as a Team: Applying Gamification to Incorporate Team-building Skills Through an 'Escape Room' Experience.

    Science.gov (United States)

    Zhang, Xiao Chi; Lee, Hyunjoo; Rodriguez, Carlos; Rudner, Joshua; Chan, Teresa M; Papanagnou, Dimitrios

    2018-03-02

    Teamwork, a skill critical for quality patient care, is recognized as a core competency by the Accreditation Council for Graduate Medical Education (ACGME). To date, there is no consensus on how to effectively teach these skills in a forum that engages learners, immerses members in life-like activities, and builds both trust and rapport. Recreational 'Escape Rooms' have gained popularity in creating a life-like environment that rewards players for working together, solving puzzles, and completing successions of mind-bending tasks in order to effectively 'escape the room' in the time allotted. In this regard, escape rooms share many parallels with the multitasking and teamwork that is essential for a successful emergency department (ED) shift. A pilot group of nine emergency medicine (EM) residents and one senior EM faculty member underwent a commercial escape room as part of a team-building exercise in January 2018. The escape room required participants to practice teamwork, communication, task delegation, and critical thinking to tackle waves of increasingly complex puzzles, ranging from hidden objects, physical object assembly (i.e., jigsaw puzzles), and symbol matching. Activities required members to recognize and utilize the collective experiences, skills, knowledge base, and physical abilities of the group. After the game, players underwent a structured 'game-master' debriefing facilitated by an employee of the commercial escape room; this was followed by a post-event survey facilitated by a faculty member, which focused on participants' feelings, experiences, and problem-solving techniques. Escape rooms afford learners the opportunity to engage in an activity that rewards teamwork and effective leadership through experiences that directly link to specific ACGME milestones and educational learning theories. EM participants were engaged in the activity and felt that the escape room reproduced an environment analogous to the ED. The debriefing that followed

  19. Exospheric density and escape fluxes of atomic isotopes on Venus and Mars

    International Nuclear Information System (INIS)

    Wallis, M.K.

    1978-01-01

    Energetic neutrals in dissociative recombinations near or above the exobase provided an important component of exospheric density and escape fluxes. Plasma thermal velocities provide the main contribution to the velocity spread and an exact integral for the escape flux applicable in marginal cases is found for a simple atmosphere and collisional cut-off. Atomic fragments from recombination of diatomic oxygen and nitrogen ions in the Venus and Mars atmospheres are examined and density integrals derived. The oxygen escape flux on Mars is half that previously estimated and there is very little isotope preference supplementing diffusive separation. However, escape of the heavier 15 N isotope is low by a factor two. Reinterpretation of its 75% enrichment as detected by Viking leads to a range 0.4-1.4 mbar for the primeval nitrogen content on Mars. (author)

  20. Inward contaminant leakage tests of the S-Tron Corporation emergency escape breathing device.

    Science.gov (United States)

    1992-04-01

    At the request of S-Tron Corporation, to support their contract with the U.S. Navy, performance tests of the Emergency Escape Breathing Device (EEBD) were conducted in the Environmental Physiology Research Section contaminant leakage chamber. Sulfur ...

  1. Escape windows to improve the size selectivity in the Baltic cod trawl fishery

    DEFF Research Database (Denmark)

    Madsen, Niels; Holst, René; Foldager, L.

    2002-01-01

    A rapid decrease of the stock of Baltic cod (Gadus morhua) has provided the incentive to improve the size selectivity in the trawl fishery. Use of escape windows is permitted in the legislation to give means of improving the size selectivity of cod as an alternative to a traditional standard codend....... The history of the use of escape windows in the Baltic Sea cod fishery is reviewed. The present escape windows do not function optimally. The objective of this new experiment was to compare an improved design of escape window, which is placed in the upper panel, with that of standard codend. Three standard...... of the codend selectivity was formulated to analyse the results and determine the effects of codend type, mesh size and other recorded variables. L50 and SR increased significantly with the mesh size. L50 was significantly increased and SR significantly reduced for a window codend with the same window mesh size...

  2. Optical escape factors for Doppler profiles in spherical, cylindrical and plane parallel geometries

    International Nuclear Information System (INIS)

    Otsuka, Masamoto.

    1977-12-01

    Optical escape factors for Doppler profiles in spherical, cylindrical and plane parallel geometries are tabulated over the range of optical depths from 10 -3 to 10 5 . Relations with the known formulae are discussed also. (auth.)

  3. Pizza or Pancake? Formation Models of Gas Escape Biosignatures in Terrestrial and Martian Sediments

    Science.gov (United States)

    Bonaccorsi, R.; Fairen, A. G.; Baker, L.; McKay, C. P.; Willson, D.

    2016-05-01

    Fine-grained sedimentary hollowed structures were imaged in Gale Crater, but no biomarkers identified to support biology. Our observation-based (gas escape) terrestrial model could inform on possible martian paleoenvironments at time of formation.

  4. Distinct Escape Pathway by Hepatitis C Virus Genotype 1a from a Dominant CD8+ T Cell Response by Selection of Altered Epitope Processing.

    Science.gov (United States)

    Walker, Andreas; Skibbe, Kathrin; Steinmann, Eike; Pfaender, Stephanie; Kuntzen, Thomas; Megger, Dominik A; Groten, Svenja; Sitek, Barbara; Lauer, Georg M; Kim, Arthur Y; Pietschmann, Thomas; Allen, Todd M; Timm, Joerg

    2016-01-01

    Antiviral CD8(+) T cells are a key component of the adaptive immune response against HCV, but their impact on viral control is influenced by preexisting viral variants in important target epitopes and the development of viral escape mutations. Immunodominant epitopes highly conserved across genotypes therefore are attractive for T cell based prophylactic vaccines. Here, we characterized the CD8(+) T cell response against the highly conserved HLA-B*51-restricted epitope IPFYGKAI1373-1380 located in the helicase domain of NS3 in people who inject drugs (PWID) exposed predominantly to HCV genotypes 1a and 3a. Despite this epitope being conserved in both genotypes, the corresponding CD8(+) T cell response was detected only in PWID infected with genotype 3a and HCV-RNA negative PWID, but not in PWID infected with genotype 1a. In genotype 3a, the detection of strong CD8(+) T cell responses was associated with epitope variants in the autologous virus consistent with immune escape. Analysis of viral sequences from multiple cohorts confirmed HLA-B*51-associated escape mutations inside the epitope in genotype 3a, but not in genotype 1a. Here, a distinct substitution in the N-terminal flanking region located 5 residues upstream of the epitope (S1368P; P = 0.00002) was selected in HLA-B*51-positive individuals. Functional assays revealed that the S1368P substitution impaired recognition of target cells presenting the endogenously processed epitope. The results highlight that, despite an epitope being highly conserved between two genotypes, there are major differences in the selected viral escape pathways and the corresponding T cell responses. HCV is able to evolutionary adapt to CD8(+) T cell immune pressure in multiple ways. Beyond selection of mutations inside targeted epitopes, this study demonstrates that HCV inhibits epitope processing by modification of the epitope flanking region under T cell immune pressure. Selection of a substitution five amino acids upstream of the

  5. The relationship between migration and development in the ESCAP region.

    Science.gov (United States)

    Skeldon, R

    1991-01-01

    The relationship between migration and development in the ESCAP region including southeast and south Asian countries and the Pacific island of Fiji, Papua New Guinea, Vanuatu, Kiribati, Samoa, and the Solomon Islands is discussed in terms of mobility transition and origin and destination factors. The changing patterns of mobility in Asia are further delineated in the discussion of internal movements and international movement. Emigration in the smaller countries of the Pacific are treated separately. Future predictions are that the Asia Pacific region will experience continued fertility decline and stabilization of low rates over the next 20 years. The declines will result in slow labor force growth, and increased demand for labor in traditional core and neocore countries as defined and presented in table form by Friedman will be heightened. International movements are likely to increase in large urban areas within destination countries. Tokyo and Singapore are the principal cities in Asia. Tokyo by restrictive government policy has limited immigration, but future labor shortages of unskilled labor from southeast Asia and China are expected. Singapore is already dependent on foreign labor by 10%. Current labor shortages have led to the creation of a growth triangle between Singapore, Indonesia, and Malaysia. Other cities expected to emerge as primary cities in international regional complexes with spillover into the hinterlands include the Hong Kong, Guangzhou, and Macau triangle in the Pearl River delta, Taipei and Seoul, and possibly Kuala Lumpur. Internal migration is expected to increase in the capital cities of Bangkok, Manila,j and centers such as Shanghai, Beijing, and other large cities of southeast Asia. These cities will be linked through the flows of skilled international migrants, which began in the 1960s and is expected to become a future major flow. Recreational and resource niches will be left in much of the Pacific, the Himalayan Kingdoms, and

  6. Outlet strut fracture and leaflet escape of Bjork-Shiley convexo-concave valve.

    Science.gov (United States)

    Uchino, Gaku; Yoshida, Hideo; Sakoda, Naoya; Hattori, Shigeru; Kawabata, Takuya; Saiki, Munehiro; Fujita, Yasufumi; Yunoki, Keiji; Hisamochi, Kunikazu; Mine, Yoshinari

    2017-06-01

    Prosthetic valve fracture is a serious complication and may arise in patient post-valve replacement. We experienced an outlet strut fracture and leaflet escape of a Bjork-Shiley convexo-concave valve. We performed an emergency redo mitral valve replacement and successfully retrieved the fractured strut and escaped leaflet from superficial femoral artery and the abdominal aorta. The patient showed an uneventful postoperative recovery.

  7. Inhibition of chaotic escape from a potential well using small parametric modulations

    International Nuclear Information System (INIS)

    Chacon, R.; Balibrea, F.; Lopez, M.A.

    1996-01-01

    It is shown theoretically for the first time that, depending on its period, amplitude, and initial phase, a periodic parametric modulation can suppress a chaotic escape from a potential well. The instance of the Helmholtz oscillator is used to demonstrate, by means of Melnikov close-quote s method, that parametric modulations of the linear or quadratic potential terms inhibit chaotic escape when certain resonance conditions are met. copyright 1996 American Institute of Physics

  8. A Direct Simulation Monte Carlo Model Of Thermal Escape From Titan

    Science.gov (United States)

    Johnson, Robert E.; Tucker, O. J.

    2008-09-01

    Recent analysis of density profiles vs. altitude from the Ion Neutral Mass Spectrometer (INMS) on Cassini (Waite et al. 2005) suggest Titan could have loss a significant amount of atmosphere in 4 Gyr at present escape rates (e.g., Johnson 2008). Strobel 2008 applied a slow hydrodynamic escape model to Titan's atmosphere using solar heating below the exobase to drive upward thermal conduction and power escape. However, near the exobase continuum models become problematic as a result of the increasing rarefaction in the atmosphere. The microscopic nature of DSMC is directly suitable to model atmosphere flow in nominal exobase region (e.g., Michael et. al. 2005). Our Preliminary DSMC models have shown no evidence for slow hydrodynamic escape of N2 and CH4 from Titan's atmosphere using boundary conditions normalized to the atmospheric properties in Strobel (2008). In this paper we use a 1D radial Direct Simulation Monte Carlo (DSMC) model of heating in Titan's upper atmosphere to estimate the escape rate as a function of the Jean's parameter. In this way we can test under what conditions the suggested deviations from Jeans escape would occur. In addition, we will be able to extract the necessary energy deposition to power the heavy molecule loss rates suggested in recent models (Strobel 2008; Yelle et. al. 2008). Michael, M. Johnson, R.E. 2005 Energy Deposition of pickup ions and heating of Titan's atmosphere. Planat. Sp. Sci. 53, 1510-1514 Johnson, R.E., "Sputtering and Heating of Titan's Upper Atmosphere", Proc Royal Soc. (London) (2008) Strobel, D.F. 2008 Titan's hydrodynamically escaping atmosphere. Icarus 193, 588-594 Yelle, R.V., J. Cui and I. C.F. Muller-Wodarg 2008 Methane Escape from Titan's Atmosphere. J. Geophys. Res in press Waite, J.H., Jr., Niemann, H.B., Yelle, R.V. et al. 2005 Ion Neutral Mass Spectrometer Results from the First Flyby of Titan. Science 308, 982-986

  9. Efektivitas Celah Pelolosan (Escape Gap) Pada Alat Tangkap Pengilar Untuk Menunjang Kelestarian Sumberdaya Ikan

    OpenAIRE

    Rezeki, Silka Tria; Syofyan, Irwandy; ', Isnaniah

    2017-01-01

    The research was conducted during of March until June 2016 in Kampar River and Laboratory of Fishing Gear and Material Faculty of Fisheries and Marine Science University of Riau. The study aim to determine the extent effectivenes of escape gap. The method used are survey and experiment method. The results of this study shown that the circles escape gap can pass the larva of fish with a value of the effectiveness has 0.89

  10. Enhancing usability of augmented-reality-based mobile escape guidelines for radioactive accidents

    International Nuclear Information System (INIS)

    Tsai, Ming-Kuan; Yau, Nie-Jia

    2013-01-01

    When radioactive accidents occur, modern tools in information technology for emergency response are good solutions to reduce the impact. Since few information-technology-based applications were developed for people during radioactive accidents, a previous study (Tsai et al., 2012) proposed augmented-reality-based mobile escape guidelines. However, because of the lack of transparent escape routes and indoor escape guidelines, the usability of the guidelines is limited. Therefore, this study introduces route planning and mobile three-dimensional (3D) graphics techniques to address the identified problems. The proposed approach could correctly present the geographical relationship from user locations to the anticipated shelters, and quickly show the floor-plan drawings as users are in the buildings. Based on the testing results, in contrast to the previous study, this study offered better escape routes, when the participants performed self-evacuation in outdoor and indoor environments. Overall, this study is not only a useful reference for similar studies, but also a beneficial tool for emergency response during radioactive accidents. -- Highlights: ► Enhancing the efficiency when people escape from radioactive accidents. ► The spatial relationship is transparently displayed in real time. ► In contrast to a previous study, this study offers better escape guidelines

  11. Escaping and repairing behaviors of the termite Odontotermes formosanus (Blattodea: Termitidae in response to disturbance

    Directory of Open Access Journals (Sweden)

    Hongpeng Xiong

    2018-03-01

    Full Text Available The escaping behavior of termites has been documented under laboratory conditions; however, no study has been conducted in a field setting due to the difficulty of observing natural behaviors inside wood or structures (e.g., nests, tunnels, etc.. The black-winged termite, Odontotermes formosanus (Shiraki, is a subterranean macrotermitine species which builds extensive mud tubes on tree trunks. In the present study, 41 videos (totaling ∼2,700 min were taken on 22 colonies/subcolonies of O. formosanus after their mud tubes were partially damaged by hand. In general, termites consistently demonstrated three phases of escape, including initiation (wandering near the mud-tube breach, individual escaping (single termites moving downward, and massive, unidirectional escaping flows (groups of termites moving downward. Downward moving and repairing were the dominant behavioral activities of individuals and were significantly more frequent than upward moving, turning/backward moving, or wandering. Interestingly, termites in escaping flows moved significantly faster than escaping individuals. Repairing behavior was observed shortly after the disturbance, and new mud tubes were preferentially constructed from the bottom up. When predators (i.e., ants were present, however, termites stopped moving and quickly sealed the mud-tube openings by capping the broken ends. Our study provides an interesting example that documents an animal (besides humans simultaneously carrying out pathway repairs and emergency evacuation without congestion.

  12. Escaping and repairing behaviors of the termite Odontotermes formosanus (Blattodea: Termitidae) in response to disturbance.

    Science.gov (United States)

    Xiong, Hongpeng; Chen, Xuan; Wen, Yuzhen; Layne, Michael; Sun, Zhaohui; Ma, Tao; Wen, Xiujun; Wang, Cai

    2018-01-01

    The escaping behavior of termites has been documented under laboratory conditions; however, no study has been conducted in a field setting due to the difficulty of observing natural behaviors inside wood or structures (e.g., nests, tunnels, etc.). The black-winged termite, Odontotermes formosanus (Shiraki), is a subterranean macrotermitine species which builds extensive mud tubes on tree trunks. In the present study, 41 videos (totaling ∼2,700 min) were taken on 22 colonies/subcolonies of O. formosanus after their mud tubes were partially damaged by hand. In general, termites consistently demonstrated three phases of escape, including initiation (wandering near the mud-tube breach), individual escaping (single termites moving downward), and massive, unidirectional escaping flows (groups of termites moving downward). Downward moving and repairing were the dominant behavioral activities of individuals and were significantly more frequent than upward moving, turning/backward moving, or wandering. Interestingly, termites in escaping flows moved significantly faster than escaping individuals. Repairing behavior was observed shortly after the disturbance, and new mud tubes were preferentially constructed from the bottom up. When predators (i.e., ants) were present, however, termites stopped moving and quickly sealed the mud-tube openings by capping the broken ends. Our study provides an interesting example that documents an animal (besides humans) simultaneously carrying out pathway repairs and emergency evacuation without congestion.

  13. Heat-induced symmetry breaking in ant (Hymenoptera: Formicidae escape behavior.

    Directory of Open Access Journals (Sweden)

    Yuan-Kai Chung

    Full Text Available The collective egress of social insects is important in dangerous situations such as natural disasters or enemy attacks. Some studies have described the phenomenon of symmetry breaking in ants, with two exits induced by a repellent. However, whether symmetry breaking occurs under high temperature conditions, which are a common abiotic stress, remains unknown. In our study, we deposited a group of Polyrhachis dives ants on a heated platform and counted the number of escaping ants with two identical exits. We discovered that ants asymmetrically escaped through two exits when the temperature of the heated platform was >32.75°C. The degree of asymmetry increased linearly with the temperature of the platform. Furthermore, the higher the temperature of heated platform was, the more ants escaped from the heated platform. However, the number of escaping ants decreased for 3 min when the temperature was higher than the critical thermal limit (39.46°C, which is the threshold for ants to endure high temperature without a loss of performance. Moreover, the ants tended to form small groups to escape from the thermal stress. A preparatory formation of ant grouping was observed before they reached the exit, indicating that the ants actively clustered rather than accidentally gathered at the exits to escape. We suggest that a combination of individual and grouping ants may help to optimize the likelihood of survival during evacuation.

  14. Flowing water affects fish fast-starts: escape performance of the Hawaiian stream goby, Sicyopterus stimpsoni.

    Science.gov (United States)

    Diamond, Kelly M; Schoenfuss, Heiko L; Walker, Jeffrey A; Blob, Richard W

    2016-10-01

    Experimental measurements of escape performance in fishes have typically been conducted in still water; however, many fishes inhabit environments with flow that could impact escape behavior. We examined the influences of flow and predator attack direction on the escape behavior of fish, using juveniles of the amphidromous Hawaiian goby Sicyopterus stimpsoni In nature, these fish must escape ambush predation while moving through streams with high-velocity flow. We measured the escape performance of juvenile gobies while exposing them to a range of water velocities encountered in natural streams and stimulating fish from three different directions. Frequency of response across treatments indicated strong effects of flow conditions and attack direction. Juvenile S. stimpsoni had uniformly high response rates for attacks from a caudal direction (opposite flow); however, response rates for attacks from a cranial direction (matching flow) decreased dramatically as flow speed increased. Mechanical stimuli produced by predators attacking in the same direction as flow might be masked by the flow environment, impairing the ability of prey to detect attacks. Thus, the likelihood of successful escape performance in fishes can depend critically on environmental context. © 2016. Published by The Company of Biologists Ltd.

  15. Epithelial cells prime the immune response to an array of gut-derived commensals towards a tolerogenic phenotype through distinct actions of thymic stromal lymphopoietin and transforming growth factor-beta

    DEFF Research Database (Denmark)

    Zeuthen, Louise Hjerrild; Fink, Lisbeth Nielsen; Frøkiær, Hanne

    2007-01-01

    in DC priming of naive T cells with elevated levels of transforming growth factor-beta (TGF-beta) and markedly reduced levels of bacteria-induced interferon-gamma production. Caco2 cell production of IL-8, thymic stromal lymphopoietin (TSLP) and TGF-beta increases upon microbial stimulation in a strain...

  16. Negative-ion states

    International Nuclear Information System (INIS)

    Compton, R.N.

    1982-01-01

    In this brief review, we discuss some of the properties of atomic and molecular negative ions and their excited states. Experiments involving photon reactions with negative ions and polar dissociation are summarized. 116 references, 14 figures

  17. Negative ion detachment processes

    International Nuclear Information System (INIS)

    Champion, R.L.; Doverspike, L.D.

    1990-10-01

    This paper discusses the following topics: H - and D - collisions with atomic hydrogen; collisional decomposition of SF 6 - ; two-electron loss processes in negative ion collisions; associative electron detachment; and negative ion desorption from surfaces

  18. Sentential Negation in English

    Science.gov (United States)

    Mowarin, Macaulay

    2009-01-01

    This paper undertakes a detailed analysis of sentential negation in the English language with Chomsky's Government-Binding theory of Transformational Grammar as theoretical model. It distinguishes between constituent and sentential negation in English. The essay identifies the exact position of Negation phrase in an English clause structure. It…

  19. Longitudinal investigation on learned helplessness tested under negative and positive reinforcement involving stimulus control.

    Science.gov (United States)

    Oliveira, Emileane C; Hunziker, Maria Helena

    2014-07-01

    In this study, we investigated whether (a) animals demonstrating the learned helplessness effect during an escape contingency also show learning deficits under positive reinforcement contingencies involving stimulus control and (b) the exposure to positive reinforcement contingencies eliminates the learned helplessness effect under an escape contingency. Rats were initially exposed to controllable (C), uncontrollable (U) or no (N) shocks. After 24h, they were exposed to 60 escapable shocks delivered in a shuttlebox. In the following phase, we selected from each group the four subjects that presented the most typical group pattern: no escape learning (learned helplessness effect) in Group U and escape learning in Groups C and N. All subjects were then exposed to two phases, the (1) positive reinforcement for lever pressing under a multiple FR/Extinction schedule and (2) a re-test under negative reinforcement (escape). A fourth group (n=4) was exposed only to the positive reinforcement sessions. All subjects showed discrimination learning under multiple schedule. In the escape re-test, the learned helplessness effect was maintained for three of the animals in Group U. These results suggest that the learned helplessness effect did not extend to discriminative behavior that is positively reinforced and that the learned helplessness effect did not revert for most subjects after exposure to positive reinforcement. We discuss some theoretical implications as related to learned helplessness as an effect restricted to aversive contingencies and to the absence of reversion after positive reinforcement. This article is part of a Special Issue entitled: insert SI title. Copyright © 2014. Published by Elsevier B.V.

  20. Negative ion sources

    International Nuclear Information System (INIS)

    Ishikawa, Junzo; Takagi, Toshinori

    1983-01-01

    Negative ion sources have been originally developed at the request of tandem electrostatic accelerators, and hundreds of nA to several μA negative ion current has been obtained so far for various elements. Recently, the development of large current hydrogen negative ion sources has been demanded from the standpoint of the heating by neutral particle beam injection in nuclear fusion reactors. On the other hand, the physical properties of negative ions are interesting in the thin film formation using ions. Anyway, it is the present status that the mechanism of negative ion action has not been so fully investigated as positive ions because the history of negative ion sources is short. In this report, the many mechanisms about the generation of negative ions proposed so far are described about negative ion generating mechanism, negative ion source plasma, and negative ion generation on metal surfaces. As a result, negative ion sources are roughly divided into two schemes, plasma extraction and secondary ion extraction, and the former is further classified into the PIG ion source and its variation and Duoplasmatron and its variation; while the latter into reflecting and sputtering types. In the second half of the report, the practical negative ion sources of each scheme are described. If the mechanism of negative ion generation will be investigated more in detail and the development will be continued under the unified know-how as negative ion sources in future, the development of negative ion sources with which large current can be obtained for any element is expected. (Wakatsuki, Y.)