bluuebunny/crossref_metadata_2025 huggingface dataset:
Induction of human interleukin 1 by bacterial and synthetic lipid A
Authors: Loppnow Harald , Brade Lore , Brade Helmut , Rietschel Ernst Theodor , Kusumoto Shoichi , Shiba Tetsuo , Flad Hans‐Dieter
Published: February 2007

Lipopolysaccharides (LPS) are well known inducers of interleukin 1 (IL1). Here we show that synthetic heptaacyl Salmonella minnesota (compound 516) and synthetic E. coli type (compound 506) lipid A, as well as monodephospho part structures thereof, are able to induce IL1 production in human mononuclear cells. The 4′‐monodephospho part structure (compound 505) was found to be the most active IL1 inducer as compared to compound 506 and the 1‐monodephospho part structure (compound 504). Synthetic lipid A precursor Ia, lacking nonhydroxylated fatty acids (compound 406), and its 1‐ or 4′‐monodephospho part structures (compounds 404 and 405) did not induce IL 1 production. IL2 is not produced during stimulation with the synthetic compounds. IL1 activity was partially heat labile and could be inhibited by a rabbit antiserum against human leukocytic pyrogen. These results show that the lipid A component of LPS is active in inducing IL 1 and that the presence of 3‐acyloxyacyl residues is necessary for IL1 induction.
Distinct short‐lived and long‐lived antibody‐producing cell populations
Authors: Ho Faith , Lortan Jennifer E. , MaClennan Ian C. M. , Khan Mahmood
Published: February 2007

This report analyzes the life span of Ig‐containing cells (IgCC) in different sites of antibody production. The experimental approach was based upon the observations that most IgCC are derived from proliferating precursors while IgCC themselves are mainly nondividing end cells. Rats were given a continuous infusion of [3H] thymidine via an osmotic pump inserted in the peritoneal cavity. At intervals of 1,3, 5 or 10 days after starting infusions, tissues were taken and analyzed by a combination of immunohistology and autoradiography to identify the proportions of IgCC which had gone through S phase of the cell cycle during the period of infusion. After 3 days infusion the median and (range) percent‐labeled IgCC in the medullary cords of mesenteric and cervical lymph nodes and the red pulp of the spleen were, respectively, 88 (81–90), 75 (66–77) and 88 (82–93). Conversely that for IgCC in bone marrow was only 13 (11–17) and that in the lamina propria of the jejunum 47 (33–68). The rate of increase in labeling of bone marrow IgCC with length of infusion was approximately linear. Extrapolation of this slope suggests that bone marrow IgCC have a life span in excess of 3 weeks. The slopes of increase in IgCC labeled with time for lymph nodes and spleen were clearly biphasic suggesting that while most IgCC in these tissues have a life span of less than 3 days, there is also a minor population of long‐lived IgCC. The lamina propria appears to have approximately equal proportions of long and short‐lived IgCC. The life span of IgCC, with the exception of IgMCC, appears to be a feature of the site of antibody production rather than the Ig class produced. Almost all IgM‐containing cells were found to be short lived.
Functional heterogeneity of nonresting B cells in human blood
Authors: Richard Yolande , Leprince Corinne , Treton Dominique , Galanaud Pierre
Published: February 2007

Among human peripheral blood B cells we localized the precursors of two interleukin‐dependent B cell activation processes: the specific response to a particulate antigen, trinitrophenylated polyacrylamide beads (TNP‐PAA) and the polyclonally induced response to pokeweed mitogen. In both cases the precursors belong to the OKB7+, sIgD−, mouse red blood cell− subpopulation. However, they differ when cell density, reflecting the stage of activation reached by B cells in peripheral blood, is considered. Only B cells of intermediate density respond to TNP‐PAA, whereas the optimal response to pokeweed mitogen is obtained with the cells displaying the lower density. The lack of response of the more dense (resting) B cells to TNP‐PAA suggests that the T dependency of this antigen is not based on linked recognition, and fits with our demonstration that this particulate antigen can trigger B cells in the presence of T cell factor. More importantly, our results show that nonresting B cells are functionally heterogeneous according to their degree of preactivation: the responsiveness to specific signals provided by a nonmitogenic hapten‐carrier conjugate would be acquired before that to polyclonal activators.
Human complement factor H: isolation of cDNA clones and partial cDNA sequence of the 38‐kDa tryptic fragment containing the binding site for C3b
Authors: Schulz Thomas F. , Schwäble Wilhelm , Stanley Keith K. , Weiß Elisabeth , Dierich Manfred P.
Published: February 2007

We isolated cDNA clones coding for the functionally important tryptic N‐terminal 38‐kDa fragment of human complement control protein factor H using polyclonal and monoclonal antibodies to screen a human liver cDNA library cloned in a bacterial expression vector, PEX‐1. By testing the reactivity of antibodies specific for the recombinant proteins produced by individual clones with proteolytic fragments of serum H the exact position of these cDNA clones within H was mapped. One clone, H‐19, coding for the 38‐kDa fragment of H was sequenced and found to code for 289 amino acids derived from the 38‐kDa N‐terminal fragment as well as for the first 108 amino acids belonging to the complementary 142‐kDa tryptic fragment. The derived protein sequence could be arranged in 6 highly homologous repeats of about 60 amino acids each, the homology between the repeats being determined by the characteristic position of cysteine, proline, glycine, tyrosine and tryptophane residues. The region coding for the epitope recognized by one of our monoclonal antibodies was localized by subcloning restriction fragments of H‐19 into the expression plasmid and testing for the expression of this epitope.
Induction of chronic idiotype suppression by ligands binding to the variable (not the constant) region of the idiotypic target
Authors: Saito Takashi , Tokuhisa Takeshi , Rajewsky Klaus
Published: February 2007

It was previously shown that in C57BL/6 mice chronic suppression of an idiotypically defined subset of λ1 chain‐bearing anti‐(4‐hydroxy‐3‐nitrophenyl)acetyl (NP) antibodies is achieved by neonatal administration of allogeneic monoclonal anti‐idiotope antibodies reactive with this subset, or by NP coupled to mouse immunoglobulin. The present data show that isologous monoclonal anti‐idiotope antibodies have the same effect. In contrast, antibodies against constant region determinants of λ1, μ or δ immunoglobulin chains failed to induce chronic suppression of the same antibody subset. Furthermore, the effect of the anti‐idiotope antibodies was neutralized by idiotypic antibodies of the IgG1 class, injected before or together with the anti‐idiotype. These results suggest that the mere complexing of idiotypic molecules on the B cell surface or in the circulation is insufficient for the induction of chronic idiotype suppression. In the present system, induction appears to require the binding of a ligand to idiotype‐bearing receptor V regions, expressed on the surface of B (or T ?) cells.
T lymphocyte control of autoreactivity: analysis with human T cell clones and limiting dilution culture
Authors: Deusch Kai , Moebius Ulrich , Zum Büschenfelde Karl‐Hermann Meyer , Meuer Stefan C.
Published: February 2007

To investigate cellular mechanisms controlling activated autoreactive T lymphocytes, a limiting dilution system was established employing cloned autoreactive major his‐tocompatibility complex class II specific lymphocytes (a2/7) as stimulator cells for autologous peripheral blood mononuclear cells. At low responder/stimulator ratios, cytotoxic effector cells were generated capable of lysing clone a2/7. Importantly, within the population of cells mediating autocytotoxic effector function, differential specificities were found to exist. The generation of such autocytotoxic T lymphocytes appears to be inhibited by an additional population of cells circulating at lower frequency suggesting that autoreactivity is controlled at distinct levels by discrete functional cellular subsets.
Interleukin 1 inhibitory activity secreted by a human myelomonocytic cell line (M20)
Authors: Barak Vivian , Treves Avraham J. , Yanai Peter , Halperin Miriam , Wasserman Dror , Biran Shoshana , Braun Sergei
Published: February 2007

Culture supernatants from a myelomonocytic cell line (M20) were found to inhibit interleukin 1 (IL 1) activity in vitro. The factor, isolated from these supernatants, inhibited augmentation of phytohemagglutinin response of mouse thymus cells induced by IL 1 derived from several established cell lines. Various IL 1‐dependent activities such as lymphocyte and fibroblast proliferation in vitro were also inhibited by the factor. The factor did not inhibit IL 2‐induced or other proliferative responses not related to IL 1. Preliminary biochemical characterization of the factor indicated that the activity resides in a protein with a molecular mass of 52 kDa.
Temporal regulation of influenza hemagglutinin expression in vaccinia virus recombinants and effects on the immune response
Authors: Coupar Barbara E. H. , Andrew Marion E. , Both Gerald W. , Boyle David B.
Published: February 2007

Regulation of the expression of influenza A/PR/8/34 hemagglutinin (HA) by the vaccinia virus promoters PF (early), P7.5 (early and late) and PL11 (late) has been demonstrated using HA‐vaccinia recombinant viruses W‐PR8‐HA3, W‐PR8‐HA6 and W‐PR8‐HA, respectively. Levels of HA on the surface of W‐PR8‐HA3 (PF)‐infected cells were lower than with either W‐PR8‐HA6 (P7.5) or W‐PR8‐HA8 (PL11). Expression of HA under the control of the late promoter PL11 was inhibited in the absence of DNA replication. All three recombinant viruses stimulated a specific antibody response in mice which was dependent on the presence of infectious virus. Recognition of HA by cytotoxic T lymphocytes (CTL) was assessed by the ability of the viruses to stimulate naive precursors in vivo, to restimulate primed CTL in vitro and by target cell recognition. HA expressed under the control of either of the promoters with early function (PF or P7.5) was recognized by CTL when W‐PR8‐HA3 or VV‐PR8‐HA6 were used to prime or restimulate splenocytes or to infect target cells. On the other hand, HA expressed by W‐PR8‐HA8 (PL11) failed to prime for a CTL response in naive CBA/H mice, was ineffective at restimulation of primed splenocytes and failed to produce target cells for recognition by specific CTL. However, in BALB/c mice W‐PR8‐HA8 did prime for a specific CTL response. These studies show that HA synthesized early in infection was recognized by both B and T cells while HA expressed after DNA replication was not generally recognized by T cells. The implications of the observations with the late promoter with respect to the use of late promoters in potential vaccinia virus‐based vaccines are considered.
Human T cell clones can induce in vitro IgE synthesis in normal B cells regardless of alloantigen recognition or specificity for peculiar antigens
Authors: Del Prete Gianfranco , Maggi Enrico , Macchia Donatella , Tiri Antonio , Parronchi Paola , Ricci Mario , Romagnani Sergio
Published: February 2007

A total number of 119 (98 CD 4+ and 21 CD 8+) T cell clones were established from tonsil and peripheral blood of three nonallergic individuals and examined for their ability to induce in vitro IgE synthesis in normal B cells.

Following preactivation for 24 h with phytohemagglutinin, 34 clones (33 CD4+ and 1 CD 8+) induced normal B cells to synthesize remarkable amounts of IgE in vitro. In contrast, equal numbers of T blasts of phytohemagglutinin‐induced T cell lines obtained from unfractionated T lymphocyte suspensions of the same donors did not show such an effect. The in vitro IgE synthesis evoked by T cell clones was detectable between day 6 and 9 and peaked on day 12. Most clones maintained their ability to stimulate in vitro IgE synthesis in repeated assays over a 3‐month period. The induction of IgE synthesis by cloned T cells did not reflect alloantigen recognition on target B cells, since T cell clones induced IgE synthesis in B cells from all randomly selected donors tested, including autologous B cells.

Preincubation for 24 h with optimal stimulatory concentrations of anti‐CD 3 (OKT 3) monoclonal antibody or its addition through the entire culture period also enabled T cell clones to stimulate de novo IgE synthesis in vitro in normal B cells. Virtually all the T cell clones active on IgE synthesis induced the in vitro production of remarkable amounts of IgM and IgG as well.

These data indicate that several human T cell clones can induce normal B cells to synthesize immunoglobulin of different classes, including IgE, regardless of alloantigen recognition on target B cells or specificity for peculiar antigens. The activity of these clones was apparently mediated by triggering of the monomorphic molecular complex CD 3, immediately before or during the incubation of T cell clones with the target B cells.
A human T cell‐specific cDNA clone (YT16) encodes a protein with extensive homology to a family of protein‐tyrosine kinases
Authors: Koga Yasuhiro , Caccia Nicolette , Toyonaga Barry , Spolski Rosanne , Yanagi Yusuke , Yoshikai Yasunobu , Mak Tak W.
Published: February 2007

We report here the isolation of a human T cell‐specific cDNA clone (YT16) that encodes a protein with extensive homology to a family of transformation and proliferation‐related protein‐tyrosine kinases (PTK). The message size of YT16 is 2.2 kb and it encodes a protein of 507 amino acids with a mol. mass of 57136 Daltons. The deduced protein sequence has an overall homology of about 50% to the viral oncogene products of src and yes. Around the PTK catalytic domain, the homologies increase to 70–80% between the deduced protein sequence of YT16 and those of the PTK viral oncogenes. Of special interest is the extensive homology between the deduced protein sequence of YT16 and that of a recently reported murine B and T lymphocyte‐specific PTK, lskT. It is possible that YT16 either encodes the human homologue of this murine gene, or a protein with similar function(s) in T cells.
HgCl2 induces nonspecific immunosuppression in Lewis rats
Authors: Pelletier Lucette , Pasquier Régine , Rossert Jérome , Druet Philippe
Published: February 2007

Brown‐Norway (BN) rats injected with HgCl2 have been previously shown to develop a variety of autoimmune abnormalities. The susceptibility of BN rats is genetically controlled, and Lewis rats bearing a different RT1 haplotype are resistant. It will be shown in the present study that the number of MRC OX‐8+ (suppressor/cytotoxic) cells increases in the spleen and lymph nodes of Lewis rats injected with HgCl2. The responsiveness to T cell mitogens and to alloantigens is concomitantly inhibited. Spleen cells from Lewis rats injected with HgCl2 fail to induce a local graft‐vs.‐host reaction. Data presented show that MRC OX‐8+ cells are involved in the immunosuppression in Lewis rats treated with HgCl2. Furthermore, lymph node cells and MRC OX‐8+ cells from these rats are able to inhibit the normal mixed lymphocyte reaction indicating that suppression is active. Thus, HgCl2 is able to trigger immune dysregulation leading either to autoimmunity or to immunosuppression depending upon the genetic background of the rat strain tested.
Homozygosity in the major histocompatibility complex region influences natural killer cell activity in man
Authors: Dubey Devendra P. , Yunis Ivan , Leslie Crystal A. , Mehta Cyrus , Yunis Edmond J.
Published: February 2007

The effect of homozygosity at HLA loci on natural killer (NK) cell activity has been examined. Lymphocytes obtained from heterozygous and homozygous individuals were incubated with 51Cr‐labeled, NK‐sensitive K562 cells at different effector/target ratios, and lytic activity was determined. Homozygous cells, obtained from individuals who are known HLA homozygotes (homozygous typing cells) and from selected families, had low NK activity compared to those heterozygous donors. This low cytotoxic activity had no correlation with sex, but did correlate with homozygosity at the HLA‐A, B and/or DR loci. A significantly lower number of cells, which bind to anti‐Leu 7 antibody, was found in homozygous donors. However, this reduced number of Leu 7+ cells could only partially account for the decrease in NK activity. These studies suggest that in some individuals homozygosity at HLA may be linked to genes that control NK activity.
β‐Cyclodextrin as a substitute for fetal calf serum in the primary antibody response in vitro
Authors: Ohmori Hitoshi , Yamamoto Itaru
Published: February 2007

Fetal calf serum (FCS) must be present at 10% in the culture medium for optimally eliciting the primary antibody response to sheep erythrocytes (SRBC) in murine lymphocytes. The response was no longer observed when FCS was reduced to less than 1%. However, we found that the addition of 250–500 μg/ml β‐cyclodextrin (β‐CD) to RPMI 1640 medium containing 1% FCS restored the immune response to a level comparable to that observed in 10% FCS‐containing medium. β‐CD did not further augment the response in the presence of 10% FCS. The order of effectiveness of various cyclodextrin compounds tested was as follows: β‐CD (100) > α‐CD(30) > γ‐CD(10) > heptakis (2,6‐O‐dimethyl)β‐CD (< 1). The in vitro antibody response varied drastically depending on the lot of FCS added to the culture medium. The important observation was that even a deficient lot of FCS could elicit the antibody response as efficiently as a good lot if it was added to the culture medium at 1% in combination with β‐CD, β‐CD was also effective in inducing the primary antibody responses to both SRBC and dinitrophenylated Ficoll in serum‐free RPMI 1640 medium containing bovine serum albumin, insulin and transferrin. In serum‐free conditions, the responses were 40–50% of those in serum‐containing medium. β‐CD did not increase the number of antibody‐forming cells nonspecifically, nor did it show a significant mitogenic activity and cytotoxicity. These data suggest that β‐CD is a useful material as a serum substitute in inducing primary antibody response in vitro.
Molecular analysis of the murine lupus‐associated anti‐self response: involvement of a large number of heavy and light chain variable region genes
Authors: Kofler Reinhard , Noonan Daniel J. , Strohal Robert , Balderas Robert S. , Moller Niels P. H. , Dixon Frank J. , Theofilopoulos Argyrios N.
Published: February 2007

The mRNA encoding heavy and light chains of a hybridoma‐derived monoclonal IgM,x anti‐immunoglobulin (rheumatoid factor) and an IgG3,x anti‐histone autoantibody from systemic lupus erythematosus and arthritis‐prone MRL/Mp‐lpr/lpr mice have been molecularily cloned, and the nucleotide sequences corresponding to their variable regions have been determined. To investigate whether autoantibodies with specificities frequently observed in lupus disease might share common structural components, the sequences obtained in this study have been compared with those of a monoclonal MRL/Mp‐lpr/lpr IgM,x anti‐DNA autoantibody previously analyzed in our laboratory (J. Exp. Med. 1985. 161: 805). The 3 immunoglobulins employed different heavy chain variable region (VH) genes belonging to the large J558 VH gene family, x light chain variable region (Vx) genes from 3 different Vx groups, and different diversity and joining segments. Our findings suggest that murine lupus‐associated autoantibodies of different specificities do not have genetic components in common to signal their self‐reactive nature and are encoded by a large number of immunoglobulin gene elements.
Induction of suppression following autologous mixed lymphocyte reaction; role of a novel 2H4 antigen
Authors: Takeuchi Tsutomu , Rudd Christopher E. , Schlossman Stuart F. , Morimoto Chikao
Published: February 2007

In this study, we have investigated the cellular and molecular basis for immunoregulatory function of T4+ cells after autologous mixed lymphocyte reaction (AMLR) activation. We demonstrated that the T4+2H4+ subset but not the T4+2H4− subset can proliferate maximally in response to autologous non‐T cells. T4+ cells activated by AMLR exerted suppressor activity on pokeweed mitogen‐driven IgG synthesis of autologous peripheral blood lymphocytes. The suppressor activity by AMLR‐activated T4+ cells required the presence of fresh T8+ cells in the secondary culture, indicating that AMLR‐activated T4+ cells functioned as a suppressor inducer rather than as a suppressor effector population. Following activation of T4+ cells in AMLR, it is the T4+2H4+ subset which induces suppression through the T8 population. Moreover, the treatment of AMLR‐activated T4+2H4+ cells with anti‐2H4 antibody, but not other antibodies, resulted in the abolishment of suppressor inducer function of such cells, suggesting that the 2H4 molecule itself may be involved in the suppressor inducer function. The 2H4 antigen on such cells was shown to be comprised of 220‐kDa and 200‐kDa glycoproteins. These results support the notion that the AMLR may play an important role in generating suppressor inducer signals and in down‐regulating the immune response following self major histocompatibility complex recognition. More importantly, the present studies indicate that the 2H4 antigen on T4 cells serves not only as a phenotypic marker of suppressor inducer cells, but may have a functionally important role itself in inducing suppression.
Supplemental zinc (Zn2+) restores antibody formation in cultures of aged spleen cells II. Effects on mediator production
Authors: Winchurch Richard A. , Togo James , Adler William H.
Published: February 2007

In vitro antibody production to T‐dependent erythrocyte antigens is depressed as a function of age. Supplementation of antibody‐forming cultures with the essential trace element zinc restores the capacity of cells from immunodepressed, aged mice to generate an antibody response. Zn2+ produces maximal enhancement of immune function when it is added to the cultures within the first 24 h. Supernatants obtained from cultures supplemented with zinc from 0–24 h contain soluble, nondialyzable factors which support enhanced antibody production in fresh cultures of cells from aged mice. Interleukin 2 levels in the supernatants from Zn2+‐supplemented cultures were not increased. However, the levels of interleukion 1 were increased approximately 300% over nonsupplemented controls and these increases corresponded with the ability of the supernatants to support antibody formation. Further studies showed that, in addition to enhancing the production of interleukin 1, Zn2+ enhanced the ability of concanavalin A‐activated T cells from aged mice to produce B cell stimulatory factor‐1.
Thymus grafts induce B cell development in nude, X‐linked immune deficient mice
Authors: Karagogeos Domna , Wortis Henry H.
Published: February 2007

Mice simultaneously expressing the mutations nude and X‐linked immune deficiency (xid) were previously shown to have pro‐B cells and/or early pre‐B cells while lacking Cμ+ and surface Ig+ cells. We now report that thymus grafts restore both T cells and B cells in nude‐xid mice. By the use of Thy‐1 and Igh allogeneic donors it was shown that both the T and B cells were host derived. The B cells had a functional phenotype typical of xid mice. It is concluded that the maturation of xid B cells past the pro‐B or early pre‐B stage is T cell dependent.
Activation of cytotoxic activity in cultures of bone marrow‐derived macrophages by indomethacin
Authors: Voth Rita , Storch Elke , Hüller Karin , Kirchner Holger
Published: February 2007

Indomethacin was tested for its ability to augment the cytotoxic capacity of cultured bone marrow‐derived macrophages (MΦ) against P815 and YAC‐1 tumor cells. MΦ were obtained from the bone marrow of C57BL/6 mice precultured for 10–14 days and were virtually 100 percent pure. By addition of indomethacin these cells were activated to kill tumor cells in a 4‐h and 18‐h Cr‐release assay. Since indomethacin is a potent inhibitor of the cyclooxygenase system, MΦ were treated with prostaglandin E2. This treatment partially reversed indomethacin‐induced cytotoxicity. Addition of other cyclooxygenase inhibitors such as acetyl‐salicylic‐acid, diclofenac or carprofen also induced cytotoxicity in bone marrow‐derived MΦ. In all experiments we failed to detect any production of interferon. Addition of anti‐interferon did not alter the cytolytic capacities demonstrating that endogenously induced interferon was not relevant in this mechanism. Our data show that cyclooxygenase inhibitors induce cytolytic activity of murine MΦ not only against a MΦ target but also against YAC‐1 cells usually considered to be targets for natural killer cells.
Soluble immune complex triggering of a respiratory burst in macrophages: the role of complex aggregation at the phagocyte surface
Authors: Vieweg Reinout , Leslie Robert G. Q.
Published: February 2007

The capacity of small, soluble immune complexes (SIC) to rearrange into larger aggregates, through additional antibody‐antigen bridge formation, on a receptor‐bearing cell surface has previously been shown to play an important role in enhancing the uptake and ingestion of SIC by macrophages and has been implicated in the efficient clearance of SIC in vivo. In this report, we extend the study to investigate the role of SIC aggregation in triggering a respiratory burst in macrophages. SIC were found to be more efficient trigger signals than nonaggregating, antigen‐free IgG oligomers of similar average size in that they induced a more rapid respiratory burst response that was between 2‐ and 6‐fold greater in magnitude. The implications of these findings are discussed.
Small Group IIa–VIa Clusters and Related Systems: A Theoretical Study of Physical Properties, Reactivity, and Electronic Spectra
Authors: Srnec Martin , Zahradník Rudolf
Published: February 2007

In the monomeric form, the title systems assume unexpected optical properties, and as oligomers they can serve as candidates for molecular devices. In bulk they are attractive in the area of material science. A broad set of quantum chemical methods ranging from density functional theory by the Hartree–Fock method and the Møller–Plesset perturbation theory to the coupled‐cluster method, in connection with nonrelativistic Dunning's basis sets as well as with relativistic SDD basis sets were used. Electronic spectra were analyzed by means of time‐dependent DFT, with the symmetry‐adapted cluster configuration interaction and with the internally contracted multireference configuration interaction. The Douglas–Kroll–Hess quasirelativistic Hamiltonian served as a basis for the estimation of the role of relativistic effects. All the diatomics representing 25 elements of a matrix formed by the combination of group IIa (Be, ..., Ba) with group VIa (O, ..., Po) atoms were characterized by calculated bond length, valence vibration, dipole moment, and the Hartree–Fock frontier orbital energies. Calculated characteristics were confronted with experimental data. The geometry of the oligomers (from dimers through hexamers) was investigated systematically, and the nature of the located stationary points on the respective potential energy surfaces was established. Special attention was paid to the four lightest elements of the group IIa–VIa matrix, i.e. BeO, BeS, MgO, and MgS. As for electronic spectra, the systems of the first column (BeO, ..., BaO), the first row (BeO, ..., BePo), and the systems of the main diagonal (BeO, ..., BaPo) were calculated in the form of monomers and dimers. Analogous calculations were performed for a few group Ia–VIIa, IIIa–Va, IVa–IVa, and IIb–VIa systems. The group IIa–VIa and IIb–VIa diatomics exhibit electronic transitions in the visible region of the spectrum, and the longest wavelength bands are located in the near‐infrared region. MgO represents an extreme with the first band appearing at about 3500 cm–1, which strictly speaking makes the use of the Born–Oppenheimer approximation questionable. Whenever experimental transitions are available, the agreement between the calculated and observed band positions is good. Passing from monomers to oligomers is always associated with a significant hypsochromic shift in the first transition.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Solvothermal Synthesis, Crystal Structure, and Thermal Stability of Three‐Layered Thioantimonate(III) Complexes: [Ni(C3H10N2)3]Sb4S7, [C4H14N2]Sb8S13·H2O, and [C6H18N2]Sb10S16·H2O
Authors: Zhang Meng , Sheng Tian Lu , Huang Xi He , Fu Rui Biao , Wang Xin , Hu Sheng Min , Xiang Sheng Chang , Wu Xin Tao
Published: February 2007

Three new thioantimonate(III) complexes [Ni(1,2‐PDA)3]Sb4S7 (1) (1,2‐PDA = 1,2‐propanediamine), [dmenH22+]Sb8S13·H2O (2) (dmen = N,N‐dimethylethylenediamine), and [deenH22+]Sb10S16·H2O (3) (deen = N,N‐diethylethylenediamine), prepared under solvothermal conditions, have been characterized by single‐crystal X‐ray diffraction, elemental analysis, and DTA‐TG measurements. In compound 1, a rectangle‐like Sb16S16 heteroring whose dimensions are about 8.1 × 14.7 Å is observed, this is the largest reported pore in layered thioantimonates to date. Further condensation of the Sb16S16 heterorings resulted in an unprecedented framework of the five‐atom thick SbxSyn– layer. In 2, a new member of SbnSn (n = 2, 3, 4, 8, 16, 30, 31, 32) heterocycles Sb15S15 heteroring has been obtained as the first example. In compound 3, the most particular feature is that when the secondary Sb–S bonds are considered the Sb2 atom becomes sevenfold coordinated.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
A 3‐D dielectrophoretic filter chip
Authors: Iliescu Ciprian , Xu Guolin , Loe Felicia Celeste , Ong Poh Lam , Tay Francis E. H.
Published: February 2007

The paper presents a 3‐D filter chip employing both mechanical and dielectrophoretic (DEP) filtration, and its corresponding microfabrication techniques. The device structure is similar to a classical capacitor: two planar electrodes, made from a stainless steel mesh, and bonded on both sides of a glass frame filled with round silica beads. The solution with the suspension of particles flows through both the mesh‐electrodes and silica beads filter. The top stainless steel mesh (with openings of 60 μm and wires of 30 μm‐thickness) provides the first stage of filtration based on mechanical trapping. A second level of filtration is based on DEP by using the nonuniformities of the electric field generated in the capacitor due to the nonuniformities of the dielectric medium. The filter can work also with DC and AC electric fields. The device was tested with yeast cells (Saccharomyces cerevisae) and achieved a maximal trapping efficiency of 75% at an applied AC voltage of 200 V and a flow rate of 0.1 mL/min, from an initial concentration of cells of 5×105 cells/mL. When the applied frequency was varieted in the range between 20 and 200 kHz, a minimal value of capture efficiency (3%) was notticed at 50 kHz, when yeast cells exhibit negative DEP and the cells are repelled in the space between the beads.
Lamination‐based rapid prototyping of microfluidic devices using flexible thermoplastic substrates
Authors: Paul Debjani , Pallandre Antoine , Miserere Sandrine , Weber Jérémie , Viovy Jean‐Louis
Published: February 2007

Transposing highly sensitive DNA separation methods (such as DNA sequencing with high read length or the detection of point mutations) to microchip format without loss of resolution requires fabrication of relatively long (approx. 10 cm) microchannels along with sharp injection bands. Conventional soft lithography methods, such as mold casting or hot‐embossing in a press, are not convenient for fabricating long channels. We have developed a lamination‐based replication technique for rapid fabrication of sealed microfluidic devices with a 10 cm long, linear separation channel. These devices are fabricated in thin cyclo‐olefin copolymer (COC) plastic substrates, thus making the device flexible and capable of assuming a range of 3‐D configurations. Due to the good optical properties of COC, this new family of devices combines multiple advantages of planar microfluidics and fused‐silica capillaries.
Isotachophoresis of proteins in a networked microfluidic chip: Experiment and 2‐D simulation
Authors: Cui Huanchun , Dutta Prashanta , Ivory Cornelius F.
Published: February 2007

This paper reports both the experimental application and 2‐D simulation of ITP of proteins in a networked microfluidic chip. Experiments demonstrate that a mixture of three fluorescent proteins can be concentrated and stacked into adjacent zones of pure protein under a constant voltage of 100 V over a 2 cm long microchannel. Measurements of the isotachophoretic velocity of the moving zones demonstrates that, during ITP under a constant voltage, the zone velocity decreases as more of the channel is occupied by the terminating electrolyte. A 2‐D ITP model based on the Nernst–Planck equations illustrates the stacking and separation features of ITP using simulations of three virtual proteins. The self‐sharpening behavior of ITP zones dispersed by a T‐junction is clearly demonstrated both by experiment and by simulation. Comparison of 2‐D simulations of ITP and zone electrophoresis (ZE) confirms that ZE lacks the ability to resharpen protein zones after they pass through a T‐junction.
Three‐dimensional immersed boundary conditions for moving solids in the lattice‐Boltzmann method
Authors: Strack O. Erik , Cook Benjamin K.
Published: February 2007

This paper establishes the range of validity for a previously published three‐dimensional moving solid boundary condition for the lattice‐Boltzmann method. This method was reasonably formulated from a mass and momentum balance perspective, but was only verified for a small range of (primarily two‐dimensional) problems. One of the advantages of this boundary condition is that it offers resolution at the sub‐grid scale, allowing for accurate and stable calculation of the force and torque for solids which are moving through a lattice, even for small solid sizes relative to the computational grid size. We verify the boundary condition for creeping flows by comparison to analytical solutions that include both the force and the torque on fixed and moving spheres, and then follow this with comparisons to experimental and empirical results for both fixed as well moving spheres in inertial flows. Finally, we compare simulation results to numerical results of other investigators for the settling of an offset sphere and the drafting–kissing–tumbling of two sedimenting spheres. We found that an accurate calculation of the collision‐operator weighting used to obtain sub‐grid‐scale resolution was necessary in order to prevent spikes in the velocities, forces, and moments when solid objects cross‐computational cells. The wide range of comparisons collected and presented in this paper can be used to establish the validity of other numerical models, in addition to the one examined here. Published in 2007 by John Wiley & Sons, Ltd.
Computation of inviscid compressible flows with the V‐SGS stabilization and YZβ shock‐capturing
Authors: Rispoli Franco , Saavedra Rafael , Corsini Alessandro , Tezduyar Tayfun E.
Published: February 2007

The YZβ shock‐capturing technique was introduced recently for use in combination with the streamline‐upwind/Petrov–Galerkin formulation of compressible flows in conservation variables. The YZβ shock‐capturing parameter is much simpler than an earlier parameter derived from the entropy variables for use in conservation variables. In this paper, we propose to use the YZβ shock‐capturing in combination with the variable subgrid scale (V‐SGS) formulation of compressible flows in conservation variables. The V‐SGS method is based on an approximation of the class of SGS models derived from the Hughes variational multiscale method. We evaluate the performance of the V‐SGS and YZβ combination in a number of standard, 2D test problems. Compared to the earlier shock‐capturing parameter derived from the entropy variables, in addition to being much simpler, the YZβ shock‐capturing parameter yields better shock quality in these test problems. Copyright © 2007 John Wiley & Sons, Ltd.
Mutations of the PTPN11 gene in therapy‐related MDS and AML with rare balanced chromosome translocations
Authors: Christiansen Debes H. , Desta Frehiwet , Andersen Mette K. , Pedersen‐Bjergaard Jens
Published: February 2007

Activating mutations of the PTPN11 gene encoding the SHP2 tyrosine phosphatase is the most common genetic abnormality in juvenile myelomonocytic leukemia and is sporadically observed in myelodysplasia (MDS) and acute myeloid leukemia (AML). An unselected series of 140 patients with therapy‐related MDS or AML were investigated for mutations of PTPN11 in Exons 3, 4, 8, and 13. Four cases had mutations of the gene; three of these had deletions or loss of chromosome arm 7q. Two cases had rare balanced translocations to chromosome band 21q22 with rearrangement of the RUNX1 gene and the other two patients had rare balanced translocations to chromosome band 3q26 with rearrangement of the EVI1 gene. The findings support cooperation between so called Class I and Class II mutations in leukemogenesis. © 2007 Wiley‐Liss, Inc.
Increasing genomic instability during premalignant neoplastic progression revealed through high resolution array‐CGH
Authors: Lai Lisa A. , Paulson Thomas G. , Li Xiaohong , Sanchez Carissa A. , Maley Carlo , Odze Robert D. , Reid Brian J. , Rabinovitch Peter S.
Published: February 2007

Chromosomal instability is regarded as an underlying mechanism of neoplastic progression, integral to the clonal selection and evolution that leads to cancer. We evaluated chromosomal instability in premalignant Barrett's esophagus tissue using high resolution Affymetrix mapping 100K SNP arrays as patients progressed through three molecular stages of disease—CDKN2ALOH only, CDKN2ALOH/TP53LOH, and CDKN2ALOH/TP53LOH with aneuploidy. Within individuals over time, we observed increases in both numbers and sizes of regions of LOH or copy number change. In the earliest CDKN2ALOH only samples, we detected few regions with both copy change and LOH, whereas copy loss and LOH were highly correlated in more advanced samples. These data indicate that genomic instability increases in severity and changes character during neoplastic progression. In addition, distinct patterns of clonal evolution could be discerned within a segment of Barrett's esophagus. Overall, this study illustrates that pre‐malignant disease can be associated with extensive instability and clonal dynamics that evolve from an initial stage characterized by small recombination‐based alterations to one with larger copy change events likely associated with mitotic instability. © 2007 Wiley‐Liss, Inc.
The impact of personality on training‐related aspects of motivation: Test of a longitudinal model
Authors: Rowold Jens
Published: February 2007

A model that proposed dispositional influences on training‐related aspects of motivation was developed. More specifically, the model predicted influences of the Big Five personality variables on motivation to learn and transfer motivation, while controlling for general attitudes toward training. The model was tested empirically, drawing on a sample of ninety‐four employees from call centers who participated in a training program. Results indicated that motivation to learn was predicted by extraversion and agreeableness, and transfer motivation was predicted by motivation to learn, extraversion, and emotional stability. The impact of extraversion on transfer motivation was partially mediated by motivation to learn. In sum, the importance of dispositional factors in training research was explored and clarified. Implications for theory and practice are discussed.
Strategies for publishing in scholarly HRD journals
Authors: Chisholm Kelley
Published: February 2007

Submitting a manuscript to a journal and having that manuscript published is a crucial step in sustaining or furthering an academic career. In addition, scholar‐practitioners and others interested in furthering their discipline's knowledge base find publishing in scholarly journals a critical activity. Success in publishing research in peer‐reviewed journals can determine whether professionals obtain or retain tenure‐track positions, as well as add to the base of knowledge that may be disseminated in the literature (Thompson, 1995). This Forum offers advice on preparing manuscripts for publication, describes the peer review process, and explains the most common reasons that manuscripts are not accepted.
Geochemistry of meteoric diagenesis in carbonate islands of the northern Bahamas: 1. Evidence from field studies
Authors: Whitaker Fiona F. , Smart Peter L.
Published: February 2007

Processes driving carbonate diagenesis in islands of the northern Bahamas are investigated using major ion, dissolved oxygen and dissolved organic carbon analyses of water samples from surface and ground waters, and measurements of soil gas P. Meteoric waters equilibrate with aragonite, but reactions are water controlled rather than mineral‐controlled and drive dissolution rather than concurrent precipitation of calcite. Surface runoff waters equilibrate with atmospheric P and rapidly recharge the vadose zone, limiting subaerial bedrock dissolution to only 6·6–15 mg l−1 Ca. P of soil gas measured in the summer wet season ((7·4 ± 3·7) × 10−3 atm) is elevated compared with that of the atmosphere, despite the thin skeletal organic nature of the soil and the discontinuous soil cover. Soil waters retained in surface pockets are equilibrated with respect to aragonite and have dissolved 51 ± 19 mg l−1 Ca. This is substantially less than the 93 ± 18 mg l−1 Ca in samples from pumping boreholes that sample meteoric waters from the freshwater lens. The high P of the freshwater lens ((16 ± 8·3) × 10−3 atm for pumping boreholes) suggests that significant additional CO2 may be derived by oxidation of soil‐ and surface‐derived organic carbon within the lens. The suboxic nature of the majority of the freshwater lens and the observed depletion in sulphate support this suggestion, and indicate that both aerobic and anaerobic oxidation may take place. Shallow lens samples from observation boreholes are calcite supersaturated and have a lower P than deeper lens waters, indicating that CO2 degasses from the water table, driving precipitation of calcite cements. We suggest that the geochemical evolution of waters in the vadose zone and upper part of the freshwater lens may be determined by the presence of a body of ground air with P controlled by production in the freshwater lens and soil and by degassing to the atmosphere. Copyright © 2007 John Wiley & Sons, Ltd.
Direct evidence for rapid and selective induction of tumor neovascular permeability by tumor necrosis factor and a novel derivative, colloidal gold bound tumor necrosis factor
Authors: Farma Jeffrey M. , Puhlmann Markus , Soriano Perry A. , Cox Derrick , Paciotti Giulio F. , Tamarkin Lawrence , Alexander H. Richard
Published: February 2007

Tumor necrosis factor (TNF) causes regression of advanced cancers when used in isolation perfusion with melphalan; evidence suggests these effects are mediated via selective yet uncharacterized actions on tumor neovasculature. A novel derivative, colloidal gold bound TNF (cAu‐TNF) has been shown to have similar antitumor effects as native TNF with less systemic toxicity in mice. These studies were done to determine their effects on tumor neovasculature, using in vivo video microscopy. Female C57BL/6 mice bearing 20 mm2 MC38 or LLC tumors that are TNF sensitive and resistant tumors, respectively, had dorsal skinfold chambers implanted. The rate of interstitial accumulation of Texas red fluorescently labeled albumin in tumor and normal vasculature was measured after intravenous TNF, cAu‐TNF or PBS. Changes in interstitial fluorescent intensity over time were quantified as a reflection of alterations in vascular permeability. MC38 bearing mice treated with TNF or cAu‐TNF demonstrated a rapid, selective and significant increase in tracer accumulation in areas of neovasculature compared to those of normal vasculature. Experiments in LLC tumor bearing mice showed similar results. Monoclonal antibody against tissue factor partially abrogated the effects of TNF on MC38 neovasculature. These data provide direct evidence that TNF and cAu‐TNF selectively and rapidly alter permeability in tumor neovasculature; a phenomenon that may be exploited to enhance selective delivery of chemotherapeutics to tumor. © 2007 Wiley‐Liss, Inc.
The differentiation antigen NY‐BR‐1 is a potential target for antibody‐based therapies in breast cancer
Authors: Seil Inka , Frei Claudia , Sültmann Holger , Knauer Shirley K. , Engels Knut , Jäger Elke , Zatloukal Kurt , Pfreundschuh Michael , Knuth Alexander , Tseng‐Chen Yao , Jungbluth Achim A. , Stauber Roland H. , Jäger Dirk
Published: February 2007

Antibody‐based cancer immunotherapy relies on the identification and characterization of target antigens and the development of potent antibodies recognizing the target. Here we report the expression analysis and molecular characterization of the differentiation antigen NY‐BR‐1, which we previously identified by using the SEREX (serological analysis of recombinant cDNA expression libraries) method. Corroborating methodologies, including mRNA quantitation and immunoblotting show that NY‐BR‐1 is strongly expressed in >70% of 129 breast tumors. Application of a NY‐BR‐1 specific antibody demonstrated NY‐BR‐1 expression in primary and metastastic breast cancers. In contrast, most of the breast cancer cell lines tested, expressed only low NY‐BR‐1 levels. Importantly, confocal microscopy revealed that ectopically expressed NY‐BR‐1 localizes to the cytoplasm and the cell membrane. NY‐BR‐1 localization in breast cancer specimens was also confirmed by immunohistochemistry. Bioinformatic analysis and deletion mutagenesis further show that NY‐BR‐1 membrane localization is mediated by 2 cis‐active membrane targeting domains. Biochemical surface labeling and FACS analysis of live cells further characterize NY‐BR‐1 as a transmembrane protein, which can be specifically recognized by the anti‐NY‐BR‐1 antibody on the surface of vital cells. The strong expression of NY‐BR‐1 in breast tumors, its cytoplasmic and membrane localization and accessibility to an ectopically applied antibody now suggest to pursue NY‐BR‐1 as a potential target for antibody‐based therapies in breast cancer patients. © 2007 Wiley‐Liss, Inc.