bluuebunny/crossref_metadata_2025_split huggingface dataset:
TGF-β1 production in inflammatory bowel disease: differing production patterns in Crohn's disease and ulcerative colitis
Authors: DEL ZOTTO B , MUMOLO G , PRONIO A M , MONTESANI C , TERSIGNI R , BOIRIVANT M 
Published: September 2003

SUMMARYTransforming growth factor-β (TGF-β) is an inhibitory cytokine recognized as a key regulator of immunological homeostasis and inflammatory responses. TGF-β is involved in experimental models of oral tolerance and in the pathogenesis of experimental colitis. Patients with inflammatory bowel disease (IBD) have inappropriate T cell responses to antigenic components of their own intestinal microflora, suggesting the presence of a disorder in the normal mucosal immune mechanism that ensures the down-regulation of responses to harmless constituents in the microflora. To evaluate the contribution of TGF-β to this imbalance, we measured TGF-β1 production by lamina propria mononuclear cells (LPMC) and T cells isolated from tissue specimens of patients with Crohn's disease (CD), ulcerative colitis (UC) and controls. Cells were cultured in the presence or absence of anti-CD2 plus anti-CD28 MoAbs and TGF-β1 production in culture supernatants was measured by ELISA. LPMC isolated from CD patients produced significantly less TGF-β1 than controls when stimulated via CD2 plus CD28 pathways (P = 0·001)] conversely, in UC patients increased production of TGF-β1 compared to controls was observed (P = 0·0005). These differences were also observed with purified lamina propria (LP) T cells in both diseases and were associated with the presence of inflammation. Thus, TGF-β1 production shows contrasting secretion in CD and in UC, probably as a consequence of the different Th polarization. The absolute or relative defect in TGF-β1 production observed in CD and UC may contribute to the perpetuation of inflammation.
Delivery of antigen in allogeneic cells preferentially generates CD4+ Th1 cells
Authors: AGREWALA J N , SUVAS S , SINGH V , VOHRA H 
Published: September 2003

SUMMARYWe have examined the possibility of evoking antigen-specific T cell immune response by using allogeneic cells as a source of adjuvant and also as a vehicle to deliver antigen. The mice were immunized with different preparations of antigen-pulsed allogeneic and syngeneic splenocytes. It was observed during the study that the animals immunized with antigen-pulsed mitomycin C treated allogeneic cells elicited antigen specific CD4+ Th1 cell response. Predominant release of IL-2, interferon (IFN)-γ and IgG2a-isotype also occurred. In contrast, mice immunized with antigen-pulsed syngeneic cells chiefly enhanced the production of interleukin (IL)-4 and IgG1-isotype. Further, allogeneic macrophages induced better T cell response than B cells or splenocytes and prominently induced the expression of B7-1 and B7-2. Immunization with antigen-pulsed macrophages provided better recall responses compared to B cells. This was manifested by the high LFA-1α and low CD45RB expression on T cells. Because it is already known that mitomycin C-treated cells undergo apoptosis and dendritic cells engulf apoptotic cells, we therefore propose that generation of T cell response using antigen-pulsed allogeneic cells may be due to the engulfment of these cells by dendritic cells, which may then process and present antigen entrapped in allogeneic cells to activate naive CD4+ T cells and differentiate them to Th1 cells. This study therefore provides a rational basis for manipulating antigen-specific responses by immunizing with antigen-pulsed allogeneic cells.
Circulating adiponectin levels during human endotoxaemia
Authors: KELLER P , MØLLER K , KRABBE K S , PEDERSEN B K 
Published: September 2003

SUMMARY
Adiponectin, an adipocytokine secreted by fat tissue, may prevent development of diabetes type II, as high adiponectin levels are linked with insulin sensitivity. In contrast, tumour necrosis factor (TNF)-α, which is also produced by fat tissue, leads to insulin resistance and furthermore inhibits adiponectin mRNA production and secretion of the protein. However, adiponectin also negatively regulates TNF-α levels. Therefore, we set out to test whether an infusion of endotoxin would influence circulating adiponectin levels in healthy human subjects. Twenty-three healthy human subjects were injected with endotoxin (2 ng/kg body weight); eight of these subjects were also injected with saline and served as controls. Plasma levels of adiponectin, TNF-α and interleukin-6 were measured at 0, 1·5, 2, 4, 8 and 24 h. TNF-α and interleukin-6 levels peaked at 1·5 h and 2 h, respectively. Control subjects injected with saline showed a decrease in adiponectin plasma levels with time (P &lt; 0·05) presumably owing to the effect of fasting or physical inactivity. However, there was no change in adiponectin plasma levels in endotoxin injected subjects, thus the effect of fasting was opposed. In conclusion, circulating adiponectin levels are reduced during a resting and fasting state, an effect reversed by endotoxin injection.
Dnase1l3 deficiency in lupus-prone MRL and NZB/W F1 mice
Authors: WILBER A , O'CONNOR T P , LU M L , KARIMI A , SCHNEIDER M C 
Published: September 2003

SUMMARY
Loss of deoxyribonuclease I (Dnase1) function is associated with systemic lupus erythematosus (SLE) in humans and mice; however, no coding mutations in Dnase1 are found in polygenic murine models. Instead, both MRL-lpr strains and NZB/W F1 hybrids are homozygous for T89I missense in the macrophage-DNASE, desoxyribonuclease I-like 3 (Dnase1l3). By in vitro expression studies, this substitution decreases this enzyme's nuclease activity against free DNA by only approximately twofold; however, the mutation has a greater effect on the capacity of media conditioned with Dnase1l3 to confer a barrier to liposomal gene transfection to HeLa cells. The 89I substitution decreases the Dnase1l3 barrier function in vitro by eightfold (P &lt; 0·01). In splenocytes and BM-derived macrophages of SLE mice, while cellular Dnase1l3 levels are induced relative to C57BL/6 (control) mice, levels of FD-nuclease activity are similar. Finally, media conditioned by MRL and NZB/W F1 macrophages, relative to control, contains a weak interferon-gamma (IFN-γ) inducible Dnase1l3-associated barrier to transfection. This barrier function is hypothesized to reflect the inability of SLE mice to degrade membrane-enveloped DNA-associated antigens, such as apoptotic bodies, which are predicted to stimulate the characteristic autoimmunity of SLE. Our results for these two generally independent models strongly suggest that Dnase1l3 deficiency increases the susceptibility of these mice to polygenic SLE.
Over-expression of interleukin 10 in mucosal T cells of patients with active ulcerative colitis
Authors: MELGAR S , YEUNG M M-W , BAS A , FORSBERG G , SUHR O , ÖBERG Å , HAMMARSTRÖM S , DANIELSSON Å , HAMMARSTRÖM M-L 
Published: September 2003

SUMMARYUlcerative colitis (UC), a chronic inflammatory bowel disease, exhibits pronounced increase of T lymphocytes in the inflamed mucosa. To understand the role of intestinal T lymphocytes in the pathogenesis of UC their cytokine production in the mucosa was analysed. Intestinal T lymphocytes of UC, Crohn's disease and control patients were analysed for cytokine mRNA levels by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) directly after isolation without in vitro stimulation. Frequencies of cytokine positive cells were determined in UC and control colon by immunomorphometry. T lymphocytes in normal colon expressed interleukin (IL)-2, interferon (IFN)-γ, tumour necrosis factor (TNF)-α and transforming growth factor (TGF)-β1, but not IL-4, IL-5 or IL-10. In UC, a highly significant increase in IL-10 mRNA levels in T lymphocytes and an increased frequency of IL-10 positive cells was seen in colon. IL-10 mRNA levels were also elevated in T lymphocytes of the non-inflamed ileum and correlated with disease activity at both locations. CD4+ T lymphocytes were the major source of IL-10 mRNA. IL-2, IFN-γ and TNF-α mRNA levels were decreased in colonic T lymphocytes, and virtually no IL-2, IFN-γ, TNF-α or TGF-β positive cells were detected in basal lymphoid aggregates. However, scattered IL-10 positive cells were found here. Lamina propria outside the aggregates contained IL-10-, IFN-γ, TNF-α and TGF-β but not IL-2 positive cells. T cells of UC patients did not express IL-4 or IL-5. Taken, together the data suggest a generalized activation of IL-10 producing CD4+ T cells along the intestine of UC patients. The local environment seems to determine the biological consequences of elevated IL-10.
Biclonal expansion of T cells infected with monoclonal Epstein–Barr virus (EBV) in a patient with chronic, active EBV infection
Authors: TOYABE S , HARADA W , UCHIYAMA M 
Published: September 2003

SUMMARYRecent studies have suggested that a high percentage of Epstein–Barr virus (EBV)-infected lymphocytes in peripheral blood of patients with chronic, active EBV infection (CAEBV) is of T cell origin. Although T cells are expanded oligoclonally in CAEBV, it is not clear whether the restricted diversity of T cells arise from immune reaction against EBV-related antigens or from proliferation of EBV-infected cells. We experienced a patient with CAEBV who had biclonal expansion of peripheral blood T cells. We identified clonotypes of these two T cell clones in detail and purified the T cell clones. EBV infected mainly the two T cell clones, whereas the viral loads in peripheral blood cells other than these T cell clones were low or undetectable. The EBV strains infecting the two T cells clones were indistinguishable from each other by a series of genotype analyses of the virus. These results suggest that the two T cell clones infected with the same monoclonal EBV proliferated in peripheral blood of the patient.
Diversity of expressed cytochrome P450 genes in the adult Mediterranean Fruit Fly, Ceratitis capitata
Authors: Field L. M. , James A. A. , Danielson P. B. , Foster J. L. M. , Cooper S. K. , Fogleman J. C. 
Published: September 2003

AbstractThe cytochrome P450s comprise a superfamily of mostly microsomal haemoproteins which play a dominant role in the metabolism of a variety of endogenous and foreign compounds. The use of a degenerate PCR primer targeted to the haem‐binding decapeptide unique to the cytochrome P450 superfamily resulted in the identification of 14 novel cytochrome P450s in the Mediterranean Fruit Fly, Ceratitis capitata. Analysis of the relative frequency of individual isoforms within the pool of isolated sequences suggests that the CYP4 and CYP6 P450 families contain the most highly expressed isoforms in adult C. capitata. Phylogenetic analyses of the conceptual amino acid translations of PCR‐amplified cDNAs provides evidence that one of isolated sequences may represent a new P450 family.
Voltage‐gated sodium channel genes hscp and hDSC1 of Heliothis virescens F. genomic organization
Authors: Field L. M. , James A. A. , Park Y. , Taylor M. F. J. , Feyereisen R. 
Published: September 2003

AbstractWe report the genomic sequence of hscp, a sodium channel α subunit gene for Heliothis virescens. A 32‐kb genomic clone and six independent RT‐PCR products covering almost the entire coding region of the gene, contained thirty‐one deduced exons with a translation of 1695 residues. Overall amino acid similarity to the para locus of Drosophila melanogaster was 86%. The transcription of the gene was complex. Alternate splicing was evident for five optional exons and a pair of mutually exclusive exons. A number of alternatively spliced mRNA revealed a deduced translation product that included only the first homology domain. We also report the first partial sequence for hDSC1, a presumed orthologous of the DSC1 sodium channel α subunit gene of D. melanogaster.
A new aminopeptidase from diamondback moth provides evidence for a gene duplication event in Lepidoptera
Authors: Field L. M. , James A. A. , Chang W. X. Z. , Gahan L. J. , Tabashnik B. E. , Heckel D. G. 
Published: September 2003

AbstractWe screened a midgut cDNA library from diamondback moth, Plutella xylostella, with a probe generated using sequence information from an aminopeptidase N gene from Manduca sexta (MsAPN‐1). The sequence recovered (PxAPN‐A) encodes a protein of 988 resides with a 60% sequence identity to MsAPN‐1. The two proteins share a signal peptide which directs processing by the endoplasmic reticulum, a C‐terminal hydrophobic region satisfying the criterion for a GPI anchor and cleavage, and the possibility of an O‐glycosylated rigid stalk attached to the GPI anchor. PxAPN‐A is more closely related to MsAPN‐1 than it is to another aminopeptidase recently reported from P. xylostella. Sequence comparisons with other species suggests that at least one aminopeptidase gene duplication occurred in an ancestral lepidopteran.
Typing of sandflies from Greece and Cyprus by DNA polymorphism of 18S rRNA gene
Authors: Field L. M. , James A. A. , Aransay A. M. , Scoulica E. , Chaniotis B. , Tselentis Y. 
Published: September 2003

AbstractA simple and reliable technique was developed to distinguish Phlebotomine sandflies by restriction fragment length polymorphism of PCR‐amplified (PCR‐RFLP) 18S rDNAs. Seven morphologically identified sandflies species from several localities of Greece and Cyprus were studied, and specific patterns were developed by double digesting amplified 18S rDNAs with Hpall and Rsal. Three additional species of the sub‐genus Larroussius were distinguished by a second double digestion with Accl and Banl. We have successfully applied the method on samples in which morphological characters were badly distinguished due to poor storage conditions and in larval stages.
Distribution and phylogeny of Wolbachia inducing thelytoky in Rhoditini and ‘Aylacini’ (Hymenoptera: Cynipidae)
Authors: Field L. M. , James A. A. , Plantard O. , Rasplus J.‐Y. , Mondor G. , Le Clainche I. , Solignac M. 
Published: September 2003

Abstract Wolbachia are endosymbiotic bacteria responsible for thelytoky in several parasitoid hymenopteran genera. After finding these micro‐organisms in some populations of Diplolepis spinosissimae (Hymenoptera: Cynipidae) where they are responsible for thelytoky through gamete duplication, we searched for Wolbachia spp. using specific PCR primers in nineteen other species of the Rhoditini tribe (rose gallwasps) and eight species of the ‘Aylacini’ tribe (gallwasps associated with herbaceous plants). Wolbachia were found in twelve Rhoditini species and four ‘Aylacini’ species. The most infected species have very few males (spanandry) and the thelytoky of infected species/arrhenotoky of uninfected species is confirmed by previous research based on the sex of the offspring of virgin females. Phylogenetic analyses based on the partial Wolbachia ftsZ gene sequences indicate that some strains associated with closely related gallwasps are phylogenetically distant, suggesting that cynipids have been affected by several infection events. In contrast, the five infected European species of Diplolepis harbour the same strain of Wolbachia.
Structural polymorphism of the luciferase gene in the firefly, Luciola lateralis
Authors: Field L. M. , James A. A. , Cho Kook Ho , Lee Jong Seob , Choi Yang Do , Boo Kyung Saeng 
Published: September 2003

AbstractTo study the structural features of genes for luciferase in Luciola lateralis, two different, functional luciferase genes, Luc1 and Luc2, were cloned and their nucleotide sequences were determined. The two genes were nearly identical, but a deletion of 128 bp was found in the 5′ upstream region of Luc2, and minor deletions and additions were also found in the 3′ downstream region. Seven base substitutions in the coding region produced two amino acid residue differences between the two genes. Southern blot analysis of genomic DNA isolated from 33 individual fireflies revealed that 26 were homozygous for the Luc1 gene and one was homozygous for Luc2. The others were heterozygotes with two, or even three, different alleles for the luciferase gene.
Moose, a new family of LTR‐retrotransposons in the mosquito Anopheles gambiae
Authors: Field L. M. , James A. A. , Biessmann H. , Walter M. F. , Le D. , Chuan S. , Yao J. G. 
Published: September 2003

AbstractA novel LTR retrotransposable element called moose has been cloned and characterized from the malaria transmitting mosquito, Anopheles gambiae. This element has all the characteristic features of LTR retroelements and is related to retroelements from other insects and nematodes, belonging to a subgroup of retroelements distinct from the copia/Ty1 and gypsy/Ty3 groups. The moose element appears to be active in A. gambiae, and strong RNA expression is detected in the male and female gonads. The use of this retroelement as a potential vector for germ line transformation is discussed.
Genetic similarity among pheromone and voltinism races of Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae)
Authors: Field L. M. , James A. A. , Marçon P. C. R. G. , Taylor D. B. , Mason C. E. , Hellmich R. L. , Siegfried B. D. 
Published: September 2003

AbstractThe genetic variability of seven European corn borer populations, Ostrinia nubilalis, from North America and Europe was assessed by polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) analysis and DNA sequencing. The nuclear ribosomal internal transcribed spacer 1 (ITS‐1) region (≈ 500 base pair [bp]) and four mitochondrial (mtDNA) regions (1550 bp total) were examined. The smartweed borer, Ostrinia obumbratalis, and south‐Western corn borer, Diatraea grandiosella, were used for comparisons. Of 106 restriction sites identified (80 in mtDNA and 26 in ITS‐1), none differentiated geographical populations, pheromone races, or voltine ecotypes of the European corn borer. The lack of variation in the ITS‐1 of European corn borer was confirmed by DNA sequence analysis. The genetic similarity of European corn borer populations, despite their wide geographical range and physiological differences, may be explained by a relatively recent origin for the voltinism and pheromone races, gene flow among races, and/or expansion from genetic bottlenecks.
Proteins from nuclear extracts of two lepidopteran cell lines recognize the ends of TTAA‐specific transposons piggyBac and tagalong
Authors: Field L. M. , James A. A. , Bauser C. A. , Elick T. A. , Fraser M. J. 
Published: September 2003

AbstractThe transposons piggyBac and tagalong are Lepidopteran transposons that exhibit extreme site‐specificity for the tetranucleotide TTAA upon insertion and excise in a characteristic precise fashion, regenerating a single TTAA target site. The precise excision of both piggyBac and tagalong can occur in the absence of factors encoded by either transposon, possibly through the recruitment of host proteins and/or cross‐mobilizing transposons. In this report, we utilize mobility shift assays and exonuclease III protection analyses to identify DNA binding activities from IPLB‐SF21AE and TN‐368 cells that are specific for piggyBac and tagalong‐terminal repeats.
Identification of a non‐LTR retrotransposon from the gypsy moth
Authors: Field L. M. , James A. A. , Garner K. J. , Slavicek J. M. 
Published: September 2003

AbstractA family of highly repetitive elements, named LDT1, has been identified in the gypsy moth, Lymantria dispar. The complete element is 5.4 kb in length and lacks long‐terminal repeats. The element contains two open reading frames with a significant amino acid sequence similarity to several non‐LTR retrotransposons. The first open reading frame contains a region that potentially encodes a polypeptide similar to DNA‐binding GAG‐like proteins. The second encodes a polypeptide resembling both endonuclease and reverse transcriptase sequences. All members of the LDT1 element family sequenced thus far have poly‐A tails or A‐rich tails of 12–18 nucleotides in length, but lack a poly‐A addition signal in the expected location. The amplification of retrotransposon insertion junction regions in different gypsy moth individuals indicates that polymorphisms exist at some of the insertion sites, suggesting that this element is or was, until recently, capable of transposition.
Microbe‐induced cytoplasmic incompatibility as a mechanism for introducing transgenes into arthropod populations
Authors: Field L. M. , James A. A. , Turelli M. , Hoffmann A. A. 
Published: September 2003

AbstractMany arthropods are infected with maternally transmitted, intracellular bacteria of the genus Wolbachia. These infections often produce ‘cytoplasmic incompatibility’ (CI)—reduced egg‐hatch frequencies when uninfected females mate with infected males or when males and females carrying different Wolbachia strains mate. Because infected females often enjoy a fitness advantage—they are effectively immune to any effects from males carrying the same Wolbachia strain—Wolbachia and associated cytoplasmic elements can spread rapidly through natural populations. Wolbachia might therefore drive transgenes associated with disease control or pest abatement into populations. In this paper, simple mathematical analyses are presented of three alternative strategies for ‘CI drive’. The analyses reveal which parameters must be estimated in order to predict population dynamics, and they demonstrate stringent requirements for initially driving and/or maintaining transgenes in target populations.
Cloning and expression of ecto 5′‐nucleotidase from the cattle tick Boophilus microplus
Authors: Field L. M. , James A. A. , Liyou N. , Hamilton S. , Elvin C. , Willadsen P. 
Published: September 2003

AbstractAlthough 5′‐nucleotidases are ubiquitous in higher vertebrates, the arthropod enzymes have been little studied. The cDNA sequence of the mature 5′‐nucleotidase from the tick Boophilus microplus was therefore determined (GenBank accession number: U80634). The enzyme has 39–41% sequence identity with the vertebrate 5′‐nucleotidases and contains binuclear metal ion binding sites. There are no significant introns within the coding region of the genomic sequence. Southern blot analysis indicates the presence of multiple related genes encoding 5′‐nucleotidases. Recombinant tick 5′‐nucleotidase was expressed in both Escherichia coli and in baculovirus‐infected insect cells. The E. coli recombinant protein was truncated, inactive and produced in abundance. The enzyme was expressed in baculovirus‐infected insect cells as a secreted, soluble, glycosylated and enzymatically active protein. This represents the first successful expression and characterization of enzymatically active recombinant 5′‐nucleotidase from any organism. Supplementation of the culture medium with 25 μm zinc resulted in a twofold increase in the activity of the expressed protein. The enzyme was purified to homogeneity. It exists under non‐denaturing conditions as a homodimer, with an apparent molecular mass of 135 kDa. The Km for the hydrolysis of AMP was 0.37 μm and the kcat= 11.5/s, in agreement with data for the native enzyme.