Lateral shift of acoustic wave at interface between double-positive and double-negative media

2006 ◽  
Vol 358 (5-6) ◽  
pp. 484-486 ◽  
Author(s):  
Lunwu Zeng ◽  
Runxia Song
Keyword(s):  
Acoustic Wave ◽  
Lateral Shift ◽  
Double Negative ◽  
Double Positive

scholarly journals Critical and Multiple Roles for the CD3ε Intracytoplasmic Tail in Double Negative to Double Positive Thymocyte Differentiation

2009 ◽  
Vol 182 (8) ◽  
pp. 4844-4853 ◽  
Author(s):  
Jean-Francois Brodeur ◽  
Samantha Li ◽  
Maria da Silva Martins ◽  
Louise Larose ◽  
Vibhuti P. Dave
Keyword(s):  
Multiple Roles ◽  
Double Negative ◽  
Double Positive ◽  
Double Positive Thymocyte ◽  
Thymocyte Differentiation

Pre-TCR signaling regulates IL-7 receptor α expression promoting thymocyte survival at the transition from the double-negative to double-positive stage

2003 ◽  
Vol 33 (7) ◽  
pp. 1968-1977 ◽  
Author(s):  
Cesar Trigueros ◽  
Katsuto Hozumi ◽  
Bruno Silva-Santos ◽  
Ludovica Bruno ◽  
Adrian C. Hayday ◽  
...  
Keyword(s):  
Double Negative ◽  
Tcr Signaling ◽  
Double Positive

scholarly journals Distinct contracted conformations of the Tcra/Tcrd locus during Tcra and Tcrd recombination

2010 ◽  
Vol 207 (9) ◽  
pp. 1835-1841 ◽  
Author(s):  
Han-Yu Shih ◽  
Michael S. Krangel
Keyword(s):  
In Situ Hybridization ◽  
Fluorescence In Situ Hybridization ◽  
Three Dimensional ◽  
Double Negative ◽  
Thymocyte Development ◽  
Double Positive ◽  
Long Distance ◽  
Large Pool ◽  
Antigen Receptor Loci

Studies have suggested that antigen receptor loci adopt contracted conformations to promote long-distance interactions between gene segments during V(D)J recombination. The Tcra/Tcrd locus is unique because it undergoes highly divergent Tcrd and Tcra recombination programs in CD4−CD8− double negative (DN) and CD4+CD8+ double positive (DP) thymocytes, respectively. Using three-dimensional fluorescence in situ hybridization, we asked whether these divergent recombination programs are supported by distinct conformational states of the Tcra/Tcrd locus. We found that the 3′ portion of the locus is contracted in DN and DP thymocytes but not in B cells. Remarkably, the 5′ portion of the locus is contracted in DN thymocytes but is decontracted in DP thymocytes. We propose that the fully contracted conformation in DN thymocytes allows Tcrd rearrangements involving Vδ gene segments distributed over 1 Mb, whereas the unique 3′-contracted, 5′-decontracted conformation in DP thymocytes biases initial Tcra rearrangements to the most 3′ of the available Vα gene segments. This would maintain a large pool of distal 5′ Vα gene segments for subsequent rounds of recombination. Thus, distinct contracted conformations of the Tcra/Tcrd locus may facilitate a transition from a Tcrd to a Tcra mode of recombination during thymocyte development.

scholarly journals Defined αβ T Cell Receptors with Distinct Ligand Specificities Do Not Require Those Ligands to Signal Double Negative Thymocyte Differentiation

2004 ◽  
Vol 199 (12) ◽  
pp. 1719-1724 ◽  
Author(s):  
Batu Erman ◽  
Terry I. Guinter ◽  
Alfred Singer
Keyword(s):  
T Cell ◽  
T Cell Development ◽  
Cell Receptor ◽  
Peptide Ligands ◽  
Double Negative ◽  
Antigen Receptors ◽  
Double Positive ◽  
Recombination Activating Gene ◽  
Thymocyte Differentiation ◽  
Deficient Mice

During T cell development in the thymus, pre–T cell receptor (TCR) complexes signal CD4− CD8− (double negative [DN]) thymocytes to differentiate into CD4+ CD8+ (double positive [DP]) thymocytes, and they generate such signals without apparent ligand engagements. Although ligand-independent signaling is unusual and might be unique to the pre-TCR, it is possible that other TCR complexes such as αβ TCR or αγ TCR might also be able to signal the DN to DP transition in the absence of ligand engagement if they were expressed on DN thymocytes. Although αγ TCR complexes efficiently signal DN thymocyte differentiation, it is not yet certain if αβ TCR complexes are also capable of signaling DN thymocyte differentiation, nor is it certain if such signaling is dependent upon ligand engagement. This study has addressed these questions by expressing defined αβ TCR transgenes in recombination activating gene 2−/− pre-Tα−/− double deficient mice. In such double deficient mice, the only antigen receptors that can be expressed are those encoded by the αβ TCR transgenes. In this way, this study definitively demonstrates that αβ TCR can in fact signal the DN to DP transition. In addition, this study demonstrates that transgenic αβ TCRs signal the DN to DP transition even in the absence of their specific MHC–peptide ligands.

A novel single step double positive double negative selection strategy for β-globin gene replacement

2006 ◽  
Vol 345 (1) ◽  
pp. 14-20 ◽  
Author(s):  
H. Khanahmad ◽  
M.R. Noori Daloii ◽  
M.A. Shokrgozar ◽  
K. Azadmanesh ◽  
A.R. Niavarani ◽  
...  
Keyword(s):  
Negative Selection ◽  
Globin Gene ◽  
Gene Replacement ◽  
Single Step ◽  
Selection Strategy ◽  
Double Negative ◽  
Double Positive

Immunophenotypic diversity and prognosis of adult T-cell leukemia/lymphoma

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 17565-17565
Author(s):  
A. Carrasco ◽  
B. Beltran ◽  
J. Malaga ◽  
G. Ferrel ◽  
H. Rios ◽  
...  
Keyword(s):  
Overall Survival ◽  
T Cell ◽  
Cell Leukaemia ◽  
Final Conclusion ◽  
Type I ◽  
Acute Type ◽  
Double Negative ◽  
Double Positive ◽  
Atll Patient ◽  
Human T Cell

17565 Background: Adult T-cell leukaemia/lymphoma (ATLL) is an aggressive disease associated with human T-cell lymphotropic virus type-I (HTLV-I) with heterogeneous clinical presentation and outcomes, described in Southern Japan, Europe, Caribbean and previously on Pacific coast of South America including Peru (EHA 2001, abst. 304). Shimoyama’s ATLL classification (BHJ 1991:79), includes four types: acute, lymphomatous, chronic and smouldering; recently a new clinical cutaneous type had been described (BJD 2005:152). Methods: We described our experienced previously (ASH 2005, abst. 4797). Herein we analyzed immunophenotypically our ATLL patient population by flow cytometry looking for aberrant phenotypes and their correlation with overall survival. The statistical method was descriptive and survival was calculated using the Kaplan-Meier method. Results: From July 1997 to March 2005 our registry had 69 cases, 37 had flow pre-treatment: acute type (n = 31) and lymphomatous (n = 6). Over our 37 flow done we were able to analysis only 33. The incidence of the typical (CD4+/CD8-) phenotype, the double-negative (CD4-/CD8-), the double-positive (CD4+/CD8+), and the CD8 positive (CD4-/CD8+) phenotypes was 58%, 12%, 15%, and 12% respectively. The median overall survival (OS) for the 33 patients was 4.1 months (range: 0.5–46.1). The patients with typical phenotypes had a median OS of 4.1 months better than the patients with the double-negative phenotype whom median OS was 2.0 (range: 1.5–9.7) but not significant. Median OS in the double positive and the CD4-/CD8+ phenotype population were 15.2 and 4.8 months respectively with no significance Conclusions: ATLL has a diversity of immunophenotype, our data suggest that there is not any correlation with survival, major accrual will gave us a final conclusion. No significant financial relationships to disclose.

scholarly journals The transcription factor Gli3 regulates differentiation of fetal CD4–CD8– double-negative thymocytes

Blood ◽  
2005 ◽  
Vol 106 (4) ◽  
pp. 1296-1304 ◽  
Author(s):  
Ariadne L. Hager-Theodorides ◽  
Johannes T. Dessens ◽  
Susan V. Outram ◽  
Tessa Crompton
Keyword(s):  
Transcription Factor ◽  
T Cell ◽  
T Cell Receptor ◽  
Cell Receptor ◽  
T Cell Differentiation ◽  
Double Negative ◽  
Thymocyte Development ◽  
Tcr Signaling ◽  
Double Positive ◽  
Dose Dependent

AbstractGlioblastoma 3 (Gli3) is a transcription factor involved in patterning and oncogenesis. Here, we demonstrate a role for Gli3 in thymocyte development. Gli3 is differentially expressed in fetal CD4–CD8– double-negative (DN) thymocytes and is most highly expressed at the CD44+ CD25– DN (DN1) and CD44–CD25– (DN4) stages of development but was not detected in adult thymocytes. Analysis of null mutants showed that Gli3 is involved at the transitions from DN1 to CD44+ CD25+ DN (DN2) cell and from DN to CD4+CD8+ double-positive (DP) cell. Gli3 is required for differentiation from DN to DP thymocyte, after pre–T-cell receptor (TCR) signaling but is not necessary for pre-TCR–induced proliferation or survival. The effect of Gli3 was dose dependent, suggesting its direct involvement in the transcriptional regulation of genes controlling T-cell differentiation during fetal development.

Scattering Characteristics of Stratified Double Negative Stacks Using the Frequency Dispersive Cold Plasma Medium

2007 ◽  
Vol 62 (5-6) ◽  
pp. 247-253 ◽  
Author(s):  
Cumali Sabah ◽  
Savas Uckun
Keyword(s):  
Wave Propagation ◽  
Electromagnetic Wave ◽  
Electric Field ◽  
Cold Plasma ◽  
Plane Electromagnetic Wave ◽  
Numerical Results ◽  
Double Negative ◽  
Plasma Medium ◽  
Double Positive ◽  
Perpendicular Polarization

We present the wave propagation through stratified double negative stacks to illustrate the scattering characteristics of their structure. The double negative stacks are modeled by using the hypothetical non-dispersive and the frequency dispersive cold plasma media. The stacks are embedded between two double positive media and the incident electric field is assumed a plane electromagnetic wave with any arbitrary polarization. By imposing the boundary conditions, the relations between the fields inside and outside the stacks can be written in a matrix form. Using this transfer matrix, the incident, reflected, and transmitted powers are derived. The variations of the powers for the stratified double negative stacks using the frequency dispersive cold plasma medium have not been investigated yet, in detail. Thus, their characteristics for the perpendicular polarization is computed and presented in numerical results with the emphasis on the plasma frequencies. It is seen from the numerical results that the stratified double negative stacks can be used as electromagnetic filters at some frequency bands.

Sign in / Sign up

Export Citation Format

Share Document