Publications by authors named "CM Thomas"

IncP-9 plasmids are best known as the vehicles for spreading biodegradation functions among Pseudomonas species but can also carry resistance determinants. New PCR primer systems targeting different replicon-specific regions were designed to allow detection of IncP-9 plasmids. Their specificity was checked against a range of IncP-9 plasmids as well as representatives of incompatibility groups IncFI, IncFII, IncN, IncQ, IncP-1alpha, IncP-1beta, IncP-2, IncP-7, IncP-13, IncW, IncU, IncX and IncZ.

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This review considers the influence of selection pressure, fitness and population structures on the evolution of mobile genetic elements (including plasmids, phage, pathogenicity islands, transposons and insertion sequences) that constitute the horizontal gene pool of bacteria. These are considered at different scales using examples from in vitro evolutionary studies of Escherichia coli and associated bacteriophage, detailed molecular analyses of the broad host-range IncP-1 plasmids, population surveys of pseudomonad plasmids and genomic comparisons of members of the Rhizobiaceae. All biological systems show genetic redundancy (the existence of allelic variation) at some population level, i.

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Objective: The purpose of this study was to evaluate the plasminogen activator system in maternal and umbilical cord plasma in patients with severe preeclampsia compared with control subjects with normotensive pregnancies.

Study Design: Maternal blood was sampled from 42 patients at a median gestational age of 32 weeks; after delivery, arterial and venous umbilical cord blood was sampled from 37 and 36 of these patients, respectively. Maternal blood from women with uncomplicated pregnancies was sampled at the gestational age of 32 weeks (n = 18, group I), and umbilical cord blood was sampled after premature deliveries of normotensive pregnancies (n = 5, group II).

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A series of dendritic cations 1-4 containing Ru(2)S(3) or Rh(2)S(3) units, either in the core or in the dendrons, has been synthesized and characterized. The X-ray crystal structure analysis of 2-Cl shows a trigonal bipyramidal Rh(2)S(3) core with propeller-like para-hydroxyphenyl substituents at the sulfur atoms. Reaction of the peripheral OH groups with diphenylphosphino benzoic acid results in the formation of phosphine-functionalized dendritic cations 5-8.

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The apical transmembrane protein Crumbs is necessary for both cell polarization and the assembly of the zonula adherens (ZA) in Drosophila epithelia. The apical spectrin-based membrane skeleton (SBMS) is a protein network that is essential for epithelial morphogenesis and ZA integrity, and exhibits close colocalization with Crumbs and the ZA in fly epithelia. These observations suggest that Crumbs may stabilize the ZA by recruiting the SBMS to the junctional region.

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The new diphosphine ligands Ph(2)PC(6)H(4)C(O)X(CH(2))(2)OC(O)C(6)H(4)PPh(2) (1: X=NH; 2: X=NPh; 3: X=O) and Ph(2)PC(6)H(4)C(O)O(CH(2))(2)O(CH(2))(2)OC(O)C(6)H(4)PPh(2) (5) as well as the monophosphine ligand Ph(2)PC(6)H(4)C(O)X(CH(2))(2)OH (4) have been prepared from 2-diphenylphosphinobenzoic acid and the corresponding amino alcohols or diols. Coordination of the diphosphine ligands to rhodium, iridium, and platinum resulted in the formation of the square-planar complexes [(Pbond;P)Rh(CO)Cl] (6: Pbond;P=1; 7: Pbond;P=2; 8: Pbond;P=3), [(Pbond;P)Rh(CO)Cl](2) (9: Pbond;P=5), [(P-P)Ir(cod)Cl] (10: Pbond;P=1; 11: Pbond;P=2; 12: Pbond;P=3), [(Pbond;P)Ir(CO)Cl] (13: Pbond;P=1; 14: Pbond;P=2; 15: Pbond;P=3), and [(Pbond;P)PtI(2)] (18: Pbond;P=2). In all complexes, the diphosphine ligands are trans coordinated to the metal center, thanks to the large spacer groups, which allow the two phosphorus atoms to occupy opposite positions in the square-planar coordination geometry.

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Plasmid pIPO2 is a cryptic, conjugative, broad-host-range plasmid isolated from the wheat rhizosphere. It efficiently self-transfers between alpha, beta and gamma Proteobacteria and has a mobilizing/retromobilizing capacity for IncQ plasmids. The complete nucleotide sequence of pIPO2 is presented on the basis of its mini-Tn5::luxABtet-tagged derivative, pIPO2T.

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Objective: To study (i) the influence of methotrexate (MTX) therapy on homocysteine and folate metabolism in patients with rheumatoid arthritis (RA), (ii) the influence of the C677T mutation in the methylenetetrahydrofolate reductase gene (MTHFR) on the change in plasma homocysteine levels during MTX treatment, and (iii) the interference of folate and homocysteine metabolism with the efficacy and toxicity of treatment with MTX.

Methods: The 113 patients enrolled in this study were participating in a 48-week, multicentre, double-blind, placebo-controlled study comparing the efficacy and toxicity of MTX treatment with and without folic or folinic acid supplementation. The MTX dose was 7.

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The KorA repressor proteins of IncP-1 plasmids belong to a growing family of plasmid-encoded repressors that regulate partitioning genes, and in the IncP-1 plasmids coordinate these with expression of replication and transfer genes as well. Both KorA(RK2) (IncP-1 alpha) and KorA(R751) (IncP-1 beta) recognise the 5'-GTTTAGCTAAAC-3' palindrome. Reporter gene assays showed that KorA proteins from these two main subgroups of IncP-1 plasmids show specificity for their own promoter/operators and this preference was confirmed with in vitro binding studies using gel mobility shift assays on one representative promoter.

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Background: The aim of this study was to analyze the concentrations of different components of the plasminogen activation system in cyst fluid from malignant, borderline and benign ovarian tumors and to compare these results with clinicopathological characteristics (FIGO staging, histological grading, residual tumor, ascites, tumor recurrence and disease-free survival).

Materials And Methods: One hundred and seven cyst fluid samples were enrolled from 25 malignant, 12 borderline and 70 benign ovarian tumors. Determination of uPA, tPA, PAI-1, PAI-2, uPA:PAI-1 complex and tPA:PAI-1 complex was performed by specific double determinant ELISAs based on the concept described previously by Grebenschikov et al.

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Little is known of how plant disease resistance (R) proteins recognize pathogens and activate plant defenses. Rcr3 is specifically required for the function of Cf-2, a Lycopersicon pimpinellifolium gene bred into cultivated tomato (Lycopersicon esculentum) for resistance to Cladosporium fulvum. Rcr3 encodes a secreted papain-like cysteine endoprotease.

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Expression of human chorionic gonadotrophin (hCG) is associated with trophoblastic, testicular and other malignancies such as bladder, pancreatic, cervical, breast and prostate cancer. In the prostate, however, hCG expression, associated with neuroendocrine cells, is also found in normal tissue. Of the six highly homologous genes that all encode the beta-subunit of hCG, the beta 7 gene is reportedly the only gene expressed in several non-transformed tissues.

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Objective: To study the effects of folic acid and zinc sulfate treatment on semen variables in fertile and subfertile men.

Design: Double-blind, placebo-controlled interventional study.

Setting: Two outpatient fertility clinics and nine midwifery practices in The Netherlands.

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Plasma lipoprotein [a] (Lp[a]) concentrations are inversely associated with, and largely determined by, apolipoprotein [a] (apo[a]) gene size, a highly polymorphic trait. We studied if, within an individual, the smaller apo[a] isoform always dominated, whether there was interaction between the two alleles, and whether these features differed between Caucasians and African Americans. We determined apo[a] gene sizes, apo[a] protein sizes and relative amounts, and plasma Lp[a] levels in 430 individuals (263 Caucasians and 167 African Americans).

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Active partitioning of low-copy number plasmids requires two proteins belonging to the ParA and ParB families and a cis-acting site which ParB acts upon. Active separation of clusters of plasmid molecules to the defined locations in the cell before cell division ensures stable inheritance of the plasmids. The central control operon of IncP-1 plasmids codes for regulatory proteins involved in the global transcriptional control of operons for vegetative replication, stable maintenance and conjugative transfer.

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The proteins encoded by chromosomal homologues of the parA and parB genes of many bacterial plasmids have been implicated in chromosome partitioning. Unlike their plasmid counterparts, mutant phenotypes produced by deleting these genes have so far been elusive or weakly expressed, except during sporulation. Here the properties of Pseudomonas putida strains with mutations in parA and parB are described.

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We have previously reported that unlinked transposed Ds elements originating from chromosome 4 of tomato preferentially inserted in chromosome 2. This observation, together with data from other studies, suggested that there may be absolute preferences for transposition, irrespective of the chromosomal location of the donor site. The aim of the present work was to verify whether the distribution of transposed Ds elements on chromosome 2 was non-random and thus whether, unlike the case in maize, unlinked transpositions in tomato are not distributed randomly.

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Objective: To assess whether counseling women planning pregnancy to start or continue folic acid supplementation improves folate status.

Methods: Women and their partners reported folic acid supplement intake in a preconceptional health questionnaire, and the women were categorized as reported "users" or "nonusers" of supplements before counseling. The use of periconceptional folic acid was addressed at a subsequent preconceptional consultation.

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A pair of genes designated parA and parB are encoded by many low copy number plasmids and bacterial chromosomes. They work with one or more cis-acting sites termed centromere-like sequences to ensure better than random predivisional partitioning of the DNA molecule that encodes them. The centromere-like sequences nucleate binding of ParB and titrate sufficient protein to create foci, which are easily visible by immuno-fluorescence microscopy.

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Folic acid supplementation around conception decreases the risk of having offspring with a neural tube defect. However, the aetiology is often still unknown. This study investigated whether spina bifida patients have lower blood folate and higher fasting and post-methionine-load plasma total homocysteine (tHcy) concentrations than control patients.

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Mupirocin (pseudomonic acid) is a polyketide antibiotic, targeting isoleucyl-tRNA synthase, and produced by Pseudomonas fluorescens NCIMB 10586. It is used clinically as a topical treatment for staphylococcal infections, particularly in contexts where there is a problem with methicillin-resistant Staphylococcus aureus (MRSA). In studying the mupirocin biosynthetic cluster the authors identified two putative regulatory genes, mupR and mupI, whose predicted amino acid sequences showed significant identity to proteins involved in quorum-sensing-dependent regulatory systems such as LasR/LuxR (transcriptional activators) and LasI/LuxI (synthases for N-acylhomoserine lactones--AHLs--that activate LasR/LuxR).

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Serum determinations of tumor markers are indispensable in the diagnosis and management of cancer, and therefore play an important role in clinical practice. After a short historical survey, we systematically review a number of contemporary aspects of serum tumor markers related to various organ systems, and briefly indicate possible future developments.

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In this study, the semen analysis results of a fertile population were compared with those from a subfertile population, in order to establish normal cut-off values for the standard semen parameters with the aid of receiver operating characteristic (ROC) curve analysis. The fertile group comprised healthy males (n = 107) without any history of fertility problems, the partners of whom had had a spontaneous pregnancy within one year of unprotected intercourse and were pregnant at the time of the male's inclusion into the study. A total of 103 males from couples attending the infertility clinic, and with an initial sperm count of <20x10(6)/ml were recruited to form the subfertile population.

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