bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of mycoplasma infection on Fc receptors for IgE of rat basophilic leukemia cells
Authors: Chan Bosco M. C. , McNeill Karol , Berczi Istvan , Froese Arnold 
Published: February 2007

AbstractEarlier studies from this laboratory had shown that rat basophilic leukemia cells carry two major receptors for IgE, named R and H, and a third minor receptor, designated 71K. It is now apparent that 71K is induced by the action of Mycoplama hyorhinis, a common contaminant of tissue cultures. This induction is reversible. Decontamination either in in vitro or in vivo leads to a disappearance of 71K and re‐infection causes its reappearance. The 71K receptor appears to be induced by the action of the mycoplasma on a surface molecule, most likely R, present on the cells at the time of infection. When receptors are occupied by IgE, 71K induction is inhibited. Other effects of mycoplasma infection include the significant reduction in the expression of transferrin receptors and increased histamine content of infected cells.
A monoclonal antibody reacting with a membrane determinant expressed on activated chicken T lymphocytes
Authors: Hála Karel , Schauenstein Konrad , Neu Nikolaus , Krömer Guido , Wolf Hugo , Böck Günther , Wick Georg 
Published: February 2007

AbstractA monoclonal antibody (INN‐CH‐16) was prepared which reacts with a cell surface antigen termed chicken activated T lymphocyte antigen. This antigen is expressed on antigen‐ or mitogen‐activated T lymphocytes and is not present on nonstimulated lymphocytes. It has an apparent molecular mass of 48‐50 kDa under reducing conditions. The value of this antibody for the immunohistochemical characterization of infiltrating cells in the thyroid glands from Obese strain chickens with spontaneous thyroiditis is demonstrated.
Cell surface and cell cycle analysis of metal‐induced murine T cell proliferation
Authors: Warner Garvin L. , Lawrence David A. 
Published: February 2007

AbstractThe heavy metale cations Pb2+, Ni2+ and Zn2+ have previously been shown to induce T cell proliferation which required the presence of both T cells and Ia+ cells at the initiation of culture. This work has examined the ability of these metals to induce cell cycle entry as determined by acridine orange cell cycle analysis. Cell surface phenotype analysis, performed on splenocytes stimulated with optimum metal concentrations (100 μM), indicated that in vitro T cell recovery (growth and/or longevity) was enhanced by Pb2+, Ni2+ and Zn2+. Furthermore, simultaneous examination of cell surface phenotype and cell cycle progression (propidium iodide) indicated that the predominant cell type proliferating in response to these metals was Thy‐1.2+. The metals differentially induced L3T4+ and Lyt‐2+ cells to enter the cell cycle. The ability of various monoclonal antibodies to modulate metal‐induced proliferation was examined. Anti‐L3T4a, anti‐I‐A and anti‐I‐E blocked metal‐induced proliferation. Anti‐Lyt‐2 only partially inhibited whereas anti‐Lyt‐1 was stimulatory. These results suggest that recognition of major histocompatibility complex‐encoded class II molecules is required for the induction of proliferation by these metals (similar to the autologous mixed lymphocyte response).
Synthetic peptides and β‐chain gene rearrangements reveal a diversified T cell repertoire for a λ light chain third hypervariable region
Authors: Bogen Bjarne , Snodgrass Ralph , Briand Jean Paul , Hannestad Kristian 
Published: February 2007

AbstractTwelve L3T4+ Ly‐2.2− subclones, derived from 4 independent BALB/c T cell lines, responded to a combination of the I‐Ed molecule and a synthetic peptide corresponding to residues 91–108 of the λ light chain from BALB/c myeloma protein M315 (α, λ2). Peptide analogues in which the mutated residues Arg95 or Asn96 were exchanged with the corresponding germ‐line‐encoded Ser95 or Thr96 had an abolished or greatly reduced capacity to stimulate T cell clones. However, responses of subclones to an analogue where the mutated Phe94 was substituted with the germ‐line‐encoded Tyr94revealed three specificity patterns: 5 clones reacted only with the λ2315 peptide, 6 clones responded equally well to both peptides and a single clone reacted better with the Tyr94 analogue. Analysis of the T cell receptor β‐chain gene rearrangements disclosed 7 distinct rearrangements, identical rearrangements only being found for subclones originating from the same line. At least 3 different Vβ genes were used. Subclones with identical or nearly identical peptide specificity, major histocompatibility complex‐restriction and alloreactivity could differ in their Vβ or Jβ gene segment utilization.
B cell dependence of the congeneic barrier towards idiotype‐carrying cells
Authors: Bösing‐Schneider Rita , Selinka Hans‐Christoph , Lehle Georg 
Published: February 2007

AbstractImmune cells transferred into nonirradiated animals of the same genotype face a barrier which severely affects their capacity to function in the host. We studied this phenomenon in allotype‐congeneic animals. When anti‐dextran immune cells of the responder strain (BALB/c‐Igha) are injected into an allotype‐congeneic host (BALB‐Ighb) the grafted cells are suppressed to give an idiotype‐positive response. This congeneic barrier of thymus‐independent immune cells is lost in mice carrying an X‐linked B cell defect: when idiotype‐positive immune cells from responder (CBA/N × BALB/C)F1 mice are transplanted into congeneic nonresponder animals (CBA/N × BALB‐Ighb)F1, female recipients are nonpermissive towards grafted cells whereas B cell‐defective male littermates allow donor cells to develop an idiotype‐positive anti‐dextran response. These results show that the congeneic barrier towards dextran‐immune cells is related to the maturation stage of B cells in the recipient. Since B cell‐defective (CBA/N × BALB/C)F1 animals do not display an anti‐idiotypic response in contrast to intact littermates and because CB16‐KN mice are nonpermissive towards CB8‐K lymphocytes, differing in VH genes only, we suggest that the “isogeneic barrier” depends on a mechanism recognizing VH structures.
Maternal transmission of idiotypic network interactions selecting available T cell repertoires
Authors: Martinez‐A. Carlos , Toribio Maria Luisa , De La Hera António , Cazenave Pierre‐André , Coutinho António 
Published: February 2007

AbstractUp to 75% of 2,4,6‐Trinitrophenyl (TNP)‐self‐specific helper T cells from normal BALB/c mice share a clonotypic determinant with the anti‐TNP myeloma protein MOPC 460, recognized by the monoclonal antibody F6(51). Immunization of adult BALB/c mice with the MOPC 460 idiotype (Ab2 mice) leads to high titers of circulating anti‐idiotypic antibodies but has no influence on the expression of the T cell clonotype. In contrast, TNP‐self‐specific helper cells prepared in progenies from Ab2females, or in BALB/c mice treated as neonatals with anti‐idiotypic antibodies, fail to express the corresponding T cell clonotype when immunized as adults. These results demonstrate the idiotype‐dependent selection of T cell repertoires early in life and their stability in adults.
Antigen‐specific activation of autoreactive B cells in normal human individuals
Authors: Logtenberg Ton , Kroon Ali , Gmelig‐Meyling Frits H. J. , Ballieux Rudy E. 
Published: February 2007

AbstractThe purpose of our study was to determine if normal human B cells can be activated to autoantibody production using an antigen‐specific system. For this purpose we investigated the in vitro antibody response to the autoantigen thyroglobulin (Tg) employing soluble or insolubilized Tg (i‐Tg) and a B cell growth and differentiation factor (BDGF) to stimulate lymphocytes from healthy individuals. Similar experiments were carried out with the xenoantigen ovalbumin (OVA). The presence of Tg and OVA‐reactive B cells was demonstrable by stimulating lymphocytes from tonsil, spleen and blood with a combination of pokeweed mitogen and formalinized Staphylococcus aureus: mitogen stimulation resulted in the generation of IgM anti‐Tg and IgM anti‐OVA antibody‐forming cells (AFC) as detected in a spot enzyme‐linked immunosorbent assay. Soluble antigen failed to induce autoantibody production. However, i‐Tg or i‐OVA did activate normal tonsil and spleen B cells. Differentiation of these activated B cells to IgM AFC required the presence of BGDF, derived from a human T hybrid clone. Preincubation experiments with the particulate autoantigen show that a specific activation signal is provided by the antigen which subsequently renders the B cells responsive to BGDF. i‐Tg‐dependent stimulation of B lymphocytes could be inhibited by adding free Tg to the cultures; the same applied to i‐OVA stimulation. We conclude that (a) the normal human B cell repertoire contains B cells that can be activated to autoantibody production by the autoantigen Tg if the necessary T cell signals are provided. Thus, these B cells are not in an inherently anergic state, (b) Similar mechanisms seem to play a role in the activation of B cells responding to i‐OVA and i‐Tg.
T11TS, the cell surface molecule binding to the “erythrocyte receptor” of T lymphocytes: cellular distribution, purification to homogeneity and biochemical properties
Authors: Hünig Thomas , Mitnacht Rita , Tiefenthaler Georg , Köhler Christine , Miyasaka Masayuki 
Published: February 2007

AbstractT11 target structure (T11TS) is a sheep cell surface glycoprotein that binds to the E receptor of human and sheep T lymphocytes. Here we report that T11TS has a broad tissue distribution, including mature and immature hematopoietic cells, vascular endothelium and smooth muscle. The density of T11TS expression was determined by Scatchard analysis with radiolabeled anti‐T11TS monoclonal antibody. Red blood cells bound 10 000, and leukocytes bound 4000 to 23 000 antibody molecules per cell. T11TS was purified to homogeneity by immune‐affinity and preparative sodium dodecyl sulfate‐polyacrylamide gel electrophoresis, and some of its biochemical properties were determined. T11TS is an acidic (pl 4.5) membrane glycoprotein that binds to concanavalin A. It has 2 or 3 N‐glycosidically linked carbohydrate side chains of the mature phenetype, no O‐linked sugars, and an apparent mol. mass of 42 kDa (glycosylated) and 32 kDa (deglycosylated). The anti‐T11TS monoclonal antibody L180/1, which blocks binding of sheep red blood cells to CD2, recognizes a protein determinant on T11TS. These findings are discussed with respect to the possible function of the CD2‐T11TS system as a set of complementary cell interaction molecules involved in T cell activation.
Requirement of H‐2 heterozygosity for autoimmunity in (NZB × NZW)F1 hybrid mice
Authors: Paper Short , Hirose Sachiko , Ueda Genjiro , Noguchi Kazuo , Okada Takashi , Sekigawa Iwao , Sato Hidetoshi , Shirai Toshikazu 
Published: February 2007

AbstractIn the F1 hybrid of autoimmune New Zealand Black (NZB) and phenotypically normal New Zealand White (NZW) mice, there occurs a severe systemic lupus erythematosus (SLE)‐like autoimmune disease more fulminant than that found in the parental NZB mice. To determine the role of the H‐2 complex in the pathogenesis of autoimmune disease of the (NZB × NZW)F1 hybrid, we developed H‐2‐congenic NZB (NZB.H‐2Z) and NZW (NZW.H‐2d) strains, and compared the degree of autoimmune features between congenic H‐2d/H‐2d and H‐2z/H‐2z homozygous F1 hybrids and the original H‐2d/H‐2z heterozygous (NZB × NZW)F1 hybrid. We found that autoimmune features such as productions of IgG class anti‐DNA antibodies and retroviral gp70 immune complexes and the development of renal disease were to a great extent reduced in both H‐2 homozygous F1 hybrids, as compared with the H‐2 heterozygous (NZB × NZW)F1 hybrid. It would thus appear that the heterozygosity of H‐2d haplotype derived from NZB and H‐2Z from NZW is essential for the autoimmune disease characteristic of the (NZB × NZW)F1 hybrid.
Large granular lymphocytes or “Pit cells” from rat liver: isolation, ultrastructural characterization and natural killer activity
Authors: Bouwens Luc , Remels Linda , Baekeland Marijke , Van Bossuyt Hans , Wisse E. 
Published: February 2007

AbstractConsiderable numbers of large granular lymphocytes (LGL) were isolated from rat liver by a simple method consisting of sinusoidal lavage at elevated (50 cm water column) perfusion pressure. This method gave a yield comparable with the enzymatic dissociation method commonly used for the isolation of nonparenchymal liver cells, but was shorter in time and had the advantage of avoiding the potentially harmful effects of the dissociating enzymes. The isolated LGL were highly cytotoxic against YAC‐1 lymphoma cells and this cytolytic activity was blocked by treatment of the effector cells with an antibody against natural killer cells (anti‐asialo GM1). We characterized the hepatic LGL as nonphagocytic, nonadherent, peroxidase‐negative and acid phosphatase‐positive cells which could be enriched in the low‐density fraction of a Percoll gradient. At the light microscopic level, they showed characteristic azurophilic granules which corresponded to strongly osmiophilic granules with a specific morphology in electron microscopy. It is concluded that these LGL are identical to the “pit cells” which were formerly described by electron microscopy in situ as normal components of the liver sinusoids and which are easily recognized by their fine structure. It is also proposed that the liver may represent one of the major natural killer organs.
Transmembrane signalling via the T11‐dependent pathway of human T cell activation. Evidence for the involvement of 1,2‐diacylglycerol and inositol phosphates
Authors: Pantaleo Giuseppe , Olive Daniel , Poggi Alessandro , Kozumbo Walter J. , Moretta Lorenzo , Moretta Alessandro 
Published: February 2007

AbstractIt has previously been shown that some anti‐T11 monoclonal antibodies, when used in combination, can activate the human T cell line Jurkat to produce interleukin 2. In this study, we investigate the mechanism by which perturbation of different epitopes of T11 molecules induces activation in Jurkat cells. We show that this activation is initiated by a T11‐mediated increase in the concentration of free cytoplasmic calcium ions ([Ca2+]i). The initial increment in [Ca2+]i can occur when extracellular Ca2+ is depleted by EGTA, indicating that Ca2+ from intracellular stores is mobilized. As an early response to extracellular signals provokes a rapid breakdown of a class of lipid known collectively as the phosphoinositides, we measured the levels of phosphatidyl‐inositol bisphosphate (PIP2) which is hydrolyzed to generate inositol triphosphates (IP3), the putative mobilizer of Ca2+ from internal stores and 1,2‐diacylglycerol (DAG), the physiological activator of protein kinase C. Monoclonal antibodies directed either against different epitopes of T11 molecules or the T3‐Ti antigen receptor complex provoke a rapid breakdown of PIP2, the parental product from which IP3 and DAG derive. In addition antibodies to either the T11 molecules or T3‐Ti antigen receptor complex induce marked elevations in IP3, other inositol phosphate compounds and DAG. Taken together, these data indicate that, during T cell activation, due to the perturbation of T11 molecules or T3‐Ti antigen receptor complex, membrane phosphoinositides are specifically hydrolyzed. This hydrolysis of phosphoinositides generates two putative second messengers such as IP3 and DAG, which mobilizes Ca2+ from intracellular stores and stimulates protein phosphorylation, respectively.
Relationship between thymus ontogeny and DNA ligase expression in the chicken
Authors: Jotereau Francine , Maniey Dominique , David Jean‐Claude 
Published: February 2007

AbstractDNA ligase expression was studied in the embryonic chicken thymus. As previously reported, during thymus ontogeny two separate and successive (8 S and 6 S) forms of enzyme are found. The switch from the heavy to the light form takes place at around 18 days of incubation in situ. The demonstration that two successive generations of thymic lymphoid precursor cells develop in the embryonic bird thymus and that the replacement of the first by the second thymocyte generation takes place at around 18 days suggested the possibility that each form of enzyme could be restricted to a given thymocyte generation. By either culturing or transplanting embryonic thymuses of different ages it appears that the switch from the heavy to the light form of DNA ligase is not related to a change over of the first by the second generation of embryonic thymocytes but rather to some maturation process of the thymic lymphocytes starting from 17 days of embryonic life. The influence of extrathymic factors on the turning on of the expression of the 6 S DNA ligase in the post‐natal environment is also suggested.
Expression of Pgp‐1 (or Ly24) by subpopulations of mouse thymocytes and activated peripheral T lymphocytes
Authors: Lynch Felicity , Chaudhri Geeta , Allan Jane E. , Doherty Peter C. , Ceredig Rhodri 
Published: February 2007

AbstractThe expression of Pgp‐1 (Ly24) by subpopulations of thymocytes was investigated and a subpopulation of Lyt‐2−/L3T4−/J11d− thymocytes was identified which contained significant numbers (80%) of Pgp‐1+ cells. Among freshly isolated lymph node T cells but not cortisone‐resistant thymocytes, Pgp‐1 expression was heterogeneous. Stimulation of T lymphocytes with either concanavalin A or the combination of phorbol myristate acetate plus calcium ionophore resulted in increased Pgp‐1 expression which was found to be regulated independently of DNA synthesis and interleukin 2 receptor expression. T cells in the cerebrospinal fluid exudate of mice infected with lymphocytic choriomeningitis virus were also found to be Pgp‐1+.
Total Synthesis ofrac‐γ‐Indomycinone by Baker–Venkataraman Rearrangement
Authors: Krohn Karsten , Tran‐Thien Hoan Trang , Vitz Jürgen , Vidal Anne 
Published: February 2007

AbstractThe total synthesis of racemic γ‐indomycinone (rac‐3) was achieved by Baker–Venkataraman rearrangement of ester11to the diketone12, acid‐catalyzed cyclization to the anthrapyranone13, followed by methyl ether cleavage and acetylation to16, selective bromination of the branched side chain with simultaneous SN1‐type hydroxy substitution to23and transesterification torac‐3. The corresponding γ‐indomycinone 11‐methyl ether (rac‐20) was prepared in a similar reaction sequence.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
CE with sequential light‐emitting diode‐induced fluorescence and electro‐chemiluminescence detections for the determination of amino acids and alkaloids
Authors: Chang Po‐Ling , Lee Kun‐Hong , Hu Cho‐Chun , Chang Huan‐Tsung 
Published: February 2007

AbstractThis paper describes the determination of alkaloids and amino acids (AAs) using CE in conjunction with sequential light‐emitting diode‐induced fluorescence (LEDIF) and electrochemiluminescence (ECL) detections. In the CE‐LEDIF‐ECL system, the ECL detector was located in the outlet of the capillary, while the LEDIF detector was positioned 12 cm from the outlet. Naphthalene‐2,3‐dicarboxaldehyde (NDA) was used to form fluorescent AA–NDA derivatives from AAs possessing primary amino groups, while Ru(bpy)32+ was used to obtain ECL signals for analytes having secondary and tertiary amino groups. In the presence of poly(ethylene oxide), we accomplished the CE‐LEDIF‐ECL separation of a mixture of 12 AA–NDA derivatives, anabasine, nicotine, and proline within 11 min. This low‐cost CE‐LEDIF‐ECL system allows the analysis of these AA–NDA derivatives and alkaloids at concentrations in the ranges of 49 nM–0.2 μM and 0.66–4.7 μM, respectively. We applied our CE‐LEDIF‐ECL system to the analysis of a urine sample and also to tobacco extracts. We obtained good qualitative and quantitative results when using this method with these analytes: the RSDs were below 3.0 and 2.8%, respectively. This CE‐LEDIF‐ECL system provides the advantages of high efficiency, speed, and sensitivity for the analysis of analytes possessing amino groups.
A new algorithm for surface tension model in moving particle methods
Authors: Zhang Shuai , Morita Koji , Fukuda Kenji , Shirakawa Noriyuki 
Published: February 2007

AbstractA new algorithm for the surface tension model was developed for moving particle methods. The algorithm is based on the link‐list search algorithm and the continuum surface tension (CST) model. The developed algorithm with the CST model was implemented to a kind of moving particle approach, the finite volume particle (FVP) method. The FVP method with the new algorithm was tested by oscillatory behaviour of a two‐dimensional droplet. The oscillatory period agrees well with analytical one, and the transient shape of the droplet is also in good agreement with that obtained by other numerical methods. The droplet impact on a liquid surface was also studied using the new algorithm. The deposition and splashing phenomena were clearly reproduced. Simulated spread radius of the splashing phenomena was consistent with a power law. Copyright © 2007 John Wiley & Sons, Ltd.
Critical evaluation of CFD codes for interfacial simulation of bubble‐train flow in a narrow channel
Authors: Özkan Furkan , Wörner Martin , Wenka Achim , Soyhan Hakan S. 
Published: February 2007

AbstractComputational fluid dynamics (CFD) codes that are able to describe in detail the dynamic evolution of the deformable interface in gas–liquid or liquid–liquid flows may be a valuable tool to explore the potential of multi‐fluid flow in narrow channels for process intensification. In the present paper, a computational exercise for co‐current bubble‐train flow in a square vertical mini‐channel is performed to investigate the performance of well‐known CFD codes for this type of flows. The computations are based on the volume‐of‐fluid method (VOF) where the transport equation for the liquid volumetric fraction is solved either by the methods involving a geometrical reconstruction of the interface or by the methods that use higher‐order difference schemes instead. The codes contributing to the present code‐to‐code comparison are an in‐house code and the commercial CFD packages CFX, FLUENT and STAR‐CD. Results are presented for two basic cases. In the first one, the flow is driven by buoyancy only, while in the second case the flow is additionally forced by an external pressure gradient. The results of the code‐to‐code comparison show that only the VOF method with interface reconstruction leads to physically sound and consistent results, whereas the use of difference schemes for the volume fraction equation shows some deficiencies. Copyright © 2007 John Wiley & Sons, Ltd.
Reactions to skill assessment: The forgotten factor in explaining motivation to learn
Authors: Bell Bradford S. , Ford J. Kevin 
Published: February 2007

AbstractThe study presented here examined the effects of trainees' reactions to skill assessment on their motivation to learn. A model was developed that suggests that two dimensions of trainees' assessment reactions, distributive justice and utility, influence training motivation and overall training effectiveness. The model was tested using a sample of individuals (N = 113) enrolled in a truck driving training program. Results revealed that trainees who perceived higher levels of distributive justice and utility had higher motivation to learn. Training motivation was found to significantly predict several measures of training effectiveness. Trainees' performance on the pretraining assessment and trait goal orientation exhibited direct and interactive effects on their reactions to the skill assessment. Implications of these findings for future research on reactions to skill assessments are identified, along with the practical implications for the design and conduct of training needs assessment.