bluuebunny/crossref_metadata_2025_split huggingface dataset:
Complex expression of natural killer receptor genes in single natural killer cells
Authors: Husain Zaheed , Alper Chester A. , Yunis Edmond J. , Dubey Devendra P. 
Published: March 2003

SummaryHuman natural killer (NK) cells express several inhibitory and non‐inhibitory NK receptors per cell. Understanding the expression patterns of these receptor genes in individual cells is important to understanding their function. Using a single‐cell reverse transcription–polymerase chain reaction (RT‐PCR) method, we analysed the expression of nine NK receptor genes in 38 resting CD56+ NK cells from peripheral blood of normal donors. We observed highly diverse patterns of receptor expression in these cells. No NK receptor is expressed universally in every CD56+ NK cell. The expressed receptor types per cell varied from two to eight. We specifically analysed the distribution of inhibitory (DL) and non‐inhibitory (DS) killer immunoglobulin‐like receptors (KIR). The frequency of individual receptor expression varied from 26% for 2DS2 to 68% for both 2DL1 and 2DL4. A comparison of the coexpression of DL and DS receptors showed a significant association in the expression of 2DL2 and 2DS2 (χ2=16·6; P<0·001) genes but no association between 2DL1 and 2DS1 or between 3DL1 and 3DS1 genes. Coexpression analysis of the 2DL1 and 2DL2 genes in 2DL4+ and 2DL4− cells showed a strong association in 2DL4+ but not in 2DL4− cells, suggesting a differential effect of the 2DL4 gene on the expression of 2DL1 and 2DL2 genes. Single‐cell RT‐PCR is a powerful tool to study multiple receptor gene expression ex vivo in individual NK cells and provides information about the expression pattern of KIR receptors that may suggest mechanisms of gene expression responsible for generation of the KIR repertoire.
Immunological weapons against acute myeloid leukaemia
Authors: Galea‐Lauri Joanna 
Published: March 2003

SummaryA better understanding of the biology of malignant cells and of the host immune system together with dramatic advances in technology have led to the design of innovative immune‐mediated approaches to control neoplastic clones, including various haematological malignancies. One of the major problems with conventional cancer therapies is their inability to eradicate residual cancer cells that are resistant to therapy, hence immune intervention might improve the clinical outcome of patients. This mini‐review will focus mainly on immunological approaches to the therapy of acute myeloid leukaemia (AML), a subset of a much larger family of leukaemias. Immune‐mediated approaches ranging from allogeneic lymphocyte transplants to cytokine therapy, immune‐gene therapy and vaccination by dendritic‐cell‐based vaccines will be discussed.
Influence of gender and interleukin‐10 deficiency on the inflammatory response during lung infection with Pseudomonas aeruginosa in mice
Authors: Guilbault Claudine , Stotland Peter , Lachance Claude , Tam Mifong , Keller Anna , Thompson‐Snipes Luann , Cowley Elizabeth , Hamilton Thomas A. , Eidelman David H. , Stevenson Mary M. , Radzioch Danuta 
Published: March 2003

SummaryCystic fibrosis females have a worse prognosis compared to male patients. Furthermore, cystic fibrosis patients infected with Pseudomonas aeruginosa have been shown to have dysregulated cytokine profiles, as higher levels of tumour necrosis factor alpha (TNF‐α), interleukin (IL)‐8, and lower levels of IL‐10 are found in the bronchoalveolar lavage fluid compared to healthy controls. The present study was aimed at investigating the importance of gender and IL‐10 in the susceptibility of C57BL/6 mice to pulmonary infection with Pseudomonas aeruginosa. We found that wildtype females were more susceptible than males to infection, as we observed greater weight loss, higher bacterial load, and inflammatory mediators in their lungs. IL‐10 knockout mice, both females and males, had higher levels of TNF‐α in the lungs compared to wildtype mice and maintained higher levels of polymorphonuclear cells and lower levels of macrophages for a longer period of time. Our results demonstrate that the number of bacteria recovered from the lungs of IL‐10 knockout male mice was significantly higher than that observed in their wildtype male counterparts and we show that neutralization of IL‐10 in infected female mice for a prolonged period of time leads to increased susceptibility to infection. Results reported in this study clearly demonstrate that females, both wildtype and IL‐10 knockout mice are more susceptible to Pseudomonas aeruginosa infection than males, and that they mount a stronger inflammatory response in the lungs.
Resistant mice lacking interleukin‐12 become susceptible to Trypanosoma cruzi infection but fail to mount a T helper type 2 response
Authors: Galvão Da Silva Ana Paula , Jacysyn Jacqueline F. , Abrahamsohn Ises De Almeida 
Published: March 2003

SummaryInterleukin‐12 (IL‐12) is essential to resistance to Trypanosoma cruzi infection because it stimulates the synthesis of interferon‐γ (IFN‐γ) that activates macrophages to a parasiticidal effect. Investigation of mice deprived of IL‐12 genes (IL‐12 knockout mice) has confirmed the important role of IL‐12 and IFN‐γ in controlling parasitism in T. cruzi infection. However, it has not yet been addressed whether a shift towards a T helper type 2 (Th2) pattern of cytokine response occurred in these mice that might have contributed to the aggravation of the infection caused by IL‐12 deprivation. We examined the course of T. cruzi (Y strain) infection and the regulation of cytokine responses and nitric oxide production in C57BL/6 IL‐12 p40‐knockout mice. The mutant mice were extremely susceptible to the infection as evidenced by increased parasitaemia, tissue parasitism and mortality in comparison with the control C57BL/6 mouse strain (wild‐type) that is resistant to T. cruzi. A severe depletion of parasite‐antigen‐specific IFN‐γ response, without an increase in IL‐4 or IL‐10 production, accompanied by reduced levels of nitric oxide production was observed in IL‐12 knockout mice. We found no evidence of a shift towards a Th2‐type cytokine response. In IL‐12 knockout mice, the residual IFN‐γ production is down‐regulated by IL‐10 but not by IL‐4 and nitric oxide production is stimulated by tumour necrosis factor‐α. Parasite‐specific immunoglobulin G1 antibody levels were similar in IL‐12 knockout and wild‐type mice, whereas IL‐12 knockout mice had much higher levels of immunoglobulin G2b.
Interleukin‐18 plays a role in both the alum‐induced T helper 2 response and the T helper 1 response induced by alum‐adsorbed interleukin‐12
Authors: Pollock Kevin G. J. , Conacher Margaret , Wei Xiao‐Qing , Alexander James , Brewer James M. 
Published: March 2003

SummaryPrevious studies have shown that the antigen‐specific T helper 2 (Th2) response induced by alum adjuvants is interleukin (IL)‐4 independent. As a role for IL‐18 in Th2 induction has recently been described, in addition to its role in enhancing Th1 responses, we have studied the Th2 response induced by ovalbumin (OVA) adsorbed to alum in wild‐type and IL‐18‐deficient mice. Our results indicate that while endogenous IL‐18 facilitates alum‐induced IL‐4 production, OVA‐specific immunoglobulin G1 (IgG1) and IgE production remain unaffected. Furthermore, antigen‐specific Th1 responses induced with alum/IL‐12‐adsorbed OVA were demonstrated to be highly IL‐18 dependent. Despite these observations, injection of BALB/c mice with exogenous IL‐18 adsorbed to alum/OVA did not alter IL‐4 or interferon‐γ production by T cells and had little effect on the relative production of IgG1/IgG2a antibody subclasses compared with alum/OVA inoculated mice. However, the previously described synergism between IL‐12 and IL‐18 in Th1 induction was evident as the Th1‐promoting activity of alum/IL‐12 against adsorbed OVA was greatly augmented by the coadministration of IL‐18. These results indicate that while alum‐induced IL‐18 can facilitate Th2 induction, the addition of exogenous IL‐18 cannot further enhance the alum‐induced Th2 response.
Telehealth acquires meanings: information and communication technologies within health policy
Authors: Klecun‐Dabrowska Ela , Cornford Tony 
Published: March 2003

Abstract.Over the last decade, British health policy has increasingly considered the role of information and information technologies in the provision of health care. Recently, there is a growing interest in new health applications, often referred to as telemedicine and telehealth, and incorporating a diverse range of services that can be provided in electronic form over various telecommunications networks. This paper discusses how such use of information and communication technologies (ICTs) in health acquires meanings through a policy process, and what implications it has for telehealth in particular. This is done through a hermeneutic exploration of four principal UK health policy papers published between 1989 and 1998.
Managing the crises in intranet implementation: a stage model
Authors: Damsgaard Jan , Scheepers Rens 
Published: March 2003

AbstractIn the seventies, Nolan was the first to address the need for a descriptive stage theory concerning the planning, organizing and controlling activities associated with managing the organizational computer resource. The arrival of newer technologies, such as those based on the Internet, calls for fresh approaches in terms of their implementation and management. Intranet technology, which is based on Internet technology, differs from other types of IT in terms of its characteristics, use and implementation. We propose a four‐stage model for intranet implementation and management. Each stage is portrayed by seven general characteristics. We propose that, in order to ensure intranet institutionalization, three existential crises must be overcome. First, if a sponsor does not nurture the intranet, it cannot evolve beyond its experimental beginnings. Second, if a critical mass of both users and content cannot be reached simultaneously, the intranet will not progress. Finally, if the intranet remains uncontrolled, it will be perceived to be useless, and therefore users will abandon it.
Sequence of a mosquito ribonucleotide reductase cDNA and evidence for gene amplification in hydroxyurea‐resistant cells
Authors: Shotkoski F. A. , Jayachandran G. , Stamatoyannopoulos G. , Fallon A. M. 
Published: March 2003

AbstractRibonucleotide reductase is essential for production of the deoxyribonucleotide substrates required for DNA synthesis in all eukaryotic cells. The full‐length cDNA encoding a mosquito ribonucleotide reductase R2 subunit was obtained from Aedes albopictus cells using a polymerase chain reaction (PCR)‐based approach. The cDNA contained 1197 nucleotides, and encoded a 398 amino acid R2 protein. Overall, mosquito R2 shared approximately 70% amino acid sequence identity with R2 proteins from vertebrates, but conservation at the N‐terminus of the protein was relatively low. The sequence of R2 cDNA was identical in hydroxyurea‐resistant mosquito cells and in wild‐type cells, while the R2 gene copy number was increased ten to twentyfold in resistant cells.
Intraspecific nucleotide variation at the pheromone binding protein locus in the turnip moth, Agrotis segetum
Authors: LaForest S. M. , Prestwich G. D. , Löfstedt C. 
Published: March 2003

AbstractInter‐ and intraspecific amino acid variability in the pheromone binding proteins (PBPs) of the Lepidoptera is believed to contribute to a molecular mechanism of pheromone blend discrimination. Messenger RNA coding for PBP sequence in Agrotis segetum (Noctuidae) was cloned, and nucleotide and inferred amino acid variation across a 769‐bp region of a PBP locus was studied in two populations. A single gene copy was fully sequenced, revealing an intron/exon structure conserved with distant saturniids. While several nucleotide substitutions are predicted to result in amino acid replacement, tests for the presence of natural selection suggest that the observed variation is neutral. A phylogenetic analysis provides evidence that the two populations are in the process of genetic isolation.
Systematic screening of Anopheles mosquito genomes yields evidence for a major clade of Pao‐like retrotransposons
Authors: Cook J. M. , Martin J. , Lewin A. , Sinden R. E. , Tristem M. 
Published: March 2003

AbstractWe developed a degenerate PCR procedure to simultaneously amplify products from divergent retrotransposon families within the genomes of Anopheles mosquitoes. The procedure required cloning of multiple PCR products, but more than half of the clones subsequently sequenced were of retrotransposon origin. These included Copia‐like and LINE retrotransposons, as well as the first Gypsy‐like retrotransposons reported from mosquitoes. Furthermore, some Anopheles retrotransposon sequences showed similarity to the divergent Pao element from the silkmoth Bombyx mori. Phylogenetic analyses provided consistently strong bootstrap support (> 95%) for a major clade of Pao‐like retrotransposons, which includes five mosquito sequences and the recently discovered Drosophila retrotransposons BEL and ninja. This appears to represent a new family of Pao‐like LTR‐retrotransposons distinct from the Copia and Gypsy families.
Subset partitioning of the ribosomal DNA small subunit and its effects on the phylogeny of the Anopheles punctulatus group
Authors: Beebe N. W. , Cooper R. D. , Morrison D. A. , Ellis J. T. 
Published: March 2003

AbstractA phylogenetic study, based on maximum parsimony, of ten species in the Anopheles punctulatus group of malaria vectors from the south‐west Pacific was performed using structural and similarity‐based DNA sequence alignments of the nuclear small ribosomal subunit (SSU = 18S). The structural alignment proved to be more informative than a computer generated similarity‐based alignment. Analyses involving the full structural sequence alignment (2169 bp) and the helical regions (1547 bp) resolved a single tree of the same topology, while analyses using the similarity based alignment could not resolve the group. Studies on the three structural domains of the nuclear rDNA SSU identified domain 2 (769 bp) as the only region informative at the sibling‐species level and resulted in the same tree as the full structural sequence and helical regions. The main conclusions of these studies were that the An. punctulatus group formed two clades: a Farauti clade containing members displaying an all black scaled proboscis (An. farauti 1–3 and 5–7) and a Punctulatus clade containing members that display some degree of white scaling on the proboscis (An. farauti 4, An. punctulatus and An. species near punctulatus). Anopheles koliensis can display either proboscis morphology and was positioned basal to the Farauti Clade. These results do not fully concord with those derived from the mitochondrial COII gene.
Ultrastructural and molecular identification of a Wolbachia endosymbiont in a spider, Nephila clavata
Authors: Woo Oh Hyun , Gwang Kim Mi , Woon Shin Sang , Sook Bae Kyung , Joon Ahn Young , Park Ho‐Yong 
Published: March 2003

Abstract Wolbachia‐like bacteria were observed in the egg cells of golden orb‐weaving spider, Nephila clavata, by means of transmission electron microscopy. The bacteria exhibited the typical morphology of Wolbachia, including three enveloping membranes. Based on the amplification and sequencing of partial 16S rDNA and ftsZ gene, the bacteria were identified as Wolbachia, intracellular, transovarially inherited α‐proteobacteria in invertebrates. Phylogenetic analysis based on 16S rDNA and ftsZ gene sequences invariably indicated that the intracellular bacteria from N. clavata belonged to group A Wolbachia, which were found only from insects. Clustering of Wolbachia from N. clavata with group A Wolbachia indicates that the bacteria were probably transferred horizontally between insects and the spider.
Secondary structure and conserved motifs of the frequently sequenced domains IV and V of the insect mitochondrial large subunit rRNA gene
Authors: Buckley T. R. , Simon C. , Flook P. K. , Misof B. 
Published: March 2003

AbstractWe have analysed over 400 partial insect mitochondrial large subunit (mit LSU) sequences in order to identify conserved motifs and secondary structures for domains IV and V of this gene. Most of the secondary structure elements described by R. R. Gutell et al. (unpublished) for the LSU were identified. However, we present structures for helices 84 and 91 that are not recognized in previous universal models. The portion of the 16S gene containing domains IV and V is frequently sequenced in insect molecular systematic studies so we have many more sequences than previous studies which focused on the complete mitochondrial LSU molecule. In addition, we have the advantage of investigating several sets of closely related taxa. Aligned sequences from thirteen insect orders and nine secondary structure diagrams are presented. These conserved sequence motifs and their associated secondary structure elements can now be used to facilitate the alignment of other insect mit LSU sequences.
Cloning of two novel P450 cDNAs from German cockroaches,Blattella germanica(L.): CYP6K1 and CYP6J1
Authors: Wen Z. , Scott J. G. 
Published: March 2003

AbstractTwo novel P450 cDNAs, CYP6K1 and CYP6J1, were isolated from German cockroaches,Blattella germanica(L). Both CYP6K1 and CYP6J1 are typical microsomal P450s and their deduced amino acid sequences share a number of common characteristics with other members of the P450 superfamily. Both CYP6K1 and CYP6J1 showed the highest per cent identity (based on the deduced amino acid sequence) to CYP6L1 fromB. germanicaand CYP6H1, a putative ecdysone 20‐hydroxylase fromLocusta migratoria. Using a CYP6K1 probe, two mRNA signals (~2.5 and ~2.1 kb) were detected in all life stages. Both signals were just detectable in the eggs and became stronger in later instars. The strongest signals were detected in the fifth and sixth instars as well as in adults. These two bands were also detected in the abdomens and in the remainder of bodies of both male and female adults. Southern blots suggest the two mRNA bands detected in the Northern blot might be a result of alternative splicing. No signal could be detected at any life stage using the CYP6J1 probe, suggesting that CYP6J1 was expressed at a low level.
Sequence analysis and expression of a virus‐like particle protein, VLP2, from the parasitic wasp Venturia canescens
Authors: Reineke A. , Asgari S. , Ma G. , Beck M. , Schmidt O. 
Published: March 2003

AbstractEndoparasitoid wasps produce maternal protein secretions, which are transported into the body of insect hosts at oviposition to regulate host physiology for successful development of their offspring. Venturia canescens calyx fluid contains so‐called virus‐like particles (VLPs) that are essential for immune evasion of the developing parasitoid inside the host. VLPs consist of four major proteins. In this paper, we describe the isolation and molecular cloning of a gene (vlp2) that is a constituent of VLPs and discuss its possible role in VLP structure and function.
Cloning of two cDNAs encoding isoforms of a pacifastin‐related precursor polypeptide in the desert locust, Schistocerca gregaria: analysis of stage‐ and tissue‐dependent expression
Authors: Simonet G. , Claeys I. , November T. , Wataleb S. , Janssen T. , Maes R. , De Loof A. , Vanden Broeck J. 
Published: March 2003

AbstractA novel serine protease inhibitor peptide family, designated as the ‘pacifastin family’, has recently been described in insects (locusts, lepidopterans) and crustaceans (crayfish). This study presents the cDNA cloning of two isoforms of SGPP‐3, a novel pacifastin‐related precursor in the desert locust, Schistocerca gregaria, which codes for three putative inhibitor peptides. The precursor isoforms differ at a single amino acid position in the third, C‐terminal peptide. Northern blot analysis confirmed the presence of two different transcripts (0.75 and 0.90 kb). Both transcripts are most abundant in the fat body and appear to be strongly regulated during the moulting cycle. In addition, the amount of transcript proved to be strictly regulated in the ovaries during the female reproductive cycle.
Response of class II molecule‐expressing cells and macrophages to cavity preparation and restoration with 4‐META /MMA‐TBB resin
Authors: Kamal A. M. M. , Okiji T. , Suda H. 
Published: March 2003

AbstractAimThe aim was to test the hypothesis that the resin and bonding agent 4‐META/MMA‐TBB (4‐META), has the potential to prevent transdentinal antigenic challenges.MethodologyClass I cavity preparation and immediate restoration with 4‐META were made in the maxillary right first molars of 36 six‐week‐old Wistar rats. Contralateral teeth with an unrestored cavity served as positive control (cavity without 4‐META) group. The maxillary first molars of 12 age‐matched normal rats (total 24 teeth) were also examined as negative control (intact tooth group). At 3 or 28 days after cavity preparation, the teeth were subjected to immunoperoxidase staining using OX6 (anticlass II molecules) and ED1 (antimacrophages) as primary antibodies.ResultsA total of 10 teeth were not available for histological examination. In the teeth filled with 4‐META at 3 days, the density of OX6+ and ED1+ cells in the coronal pulp was significantly higher than that in the intact tooth group. At 28 days, formation of sound reparative dentine was noted and the density of the immunocompetent cells was comparable to the intact teeth. In the teeth without 4‐META at 3 days, pulpal abscess was observed in 14 out of 16 and the density of OX6+ and ED1+ cells was significantly increased (P < 0.001, paired t‐test) compared with the 4‐META group. Partial pulp necrosis had developed in the teeth without 4‐META at 28 days.ConclusionsRestoration with 4‐META significantly reduced transdentinal antigenic challenges. This property may have special implications for 4‐META’s capacity to protect the dentine/pulp complex.
Effect of Nd:YAG laser irradiation on the apical leakage of obturated root canals: an electrochemical study
Authors: Park D. S. , Lee H. J. , Yoo H. M. , Oh T. S. 
Published: March 2003

AbstractAimThe purpose of this laboratory study was to evaluate the effect of Nd:YAG laser irradiation on the apical leakage of obturated root canals using an electrochemical method.MethodologyForty extracted single‐rooted teeth were selected and the anatomic crown of each tooth was removed. The specimens were randomly divided into four groups. In group 1, the root canals were prepared with K‐files and irradiated with Nd:YAG laser (5 W, 20 Hz) via a 300 µm optical fibre. Then the root canals were obturated with laterally condensed gutta‐percha and Pulp Canal Sealer EWT. In group 2, the root canals were treated with the same method as those of group 1 but without laser irradiation. In group 3, the root canals were prepared with ProFiles, laser irradiated and then obturated with vertically condensed gutta‐percha and Pulp Canal Sealer EWT. In group 4, the root canals were treated with the same method as those of group 3 but without laser irradiation. The electric resistance between standard and experimental electrodes in the canals was measured over a period of 10 days.ResultsAt 2 h, groups 1 and 3 irradiated with laser had significantly less apical leakage than group 2 (P < 0.05). After 10 days, group 4 had the highest leakage, followed by groups 2, 1 and 3; the differences between the groups was statistically significant (P < 0.05).ConclusionsLaser irradiation following root canal preparation reduced apical leakage following root canal obturation.