Cloning and characterization of a Rhizobium leguminosarum gene encoding a bacteriocin with similarities to RTX toxins.

A 3-kb region containing the determinant for bacteriocin activity from Rhizobium leguminosarum 248 was isolated and characterized by Tn5 insertional mutagenesis and DNA sequencing. Southern hybridizations showed that this bacteriocin was encoded on the plasmid pRL1JI and that homologous loci were not found in other unrelated R. leguminosarum strains.

Predictive value of pulmonary venous flow patterns in detecting mitral regurgitation and left ventricular abnormalities.

Objective: To determine whether abnormalities in pulmonary venous flow (PVF) patterns detected by transesophageal echocardiography (TEE) correlate with the severity of mitral regurgitation (MR) or the presence of left ventricular (LV) abnormalities, and to demonstrate whether a normal PVF pattern predicts the absence of structural heart disease.

Design: Review of all TEEs performed at a tertiary care cardiac hospital over a four-month period.

Patients: Among 195 studies, 100 fulfilled the inclusion criteria.

Signalling by the RET receptor tyrosine kinase and its role in the development of the mammalian enteric nervous system.

RET is a member of the receptor tyrosine kinase (RTK) superfamily, which can transduce signalling by glial cell line-derived neurotrophic factor (GDNF) and neurturin (NTN) in cultured cells. In order to determine whether in addition to being sufficient, RET is also necessary for signalling by these growth factors, we studied the response to GDNF and NTN of primary neuronal cultures (peripheral sensory and central dopaminergic neurons) derived from wild-type and RET-deficient mice. Our experiments show that absence of a functional RET receptor abrogates the biological responses of neuronal cells to both GDNF and NTN.

The impact of reminder letters on attendance for breast cancer screening.

Objective: The aims of this investigation was to analyse the response to second and third postal invitations from a group of patients previously invited for mammographic screening and to identify any demographic differences between responders and non-responders.

Subjects: The subjects were females aged 50-64 yr resident in 6 adjacent District Electoral Divisions (DEDs) in North Dublin where screening had not been carried out prior to the study.

Method: Non-responders to an invitation for screening were re-invited by computer-generated letter to attend for screening 6 weeks after issue of the first invitation and a final invitation was issued at 12 weeks.

Specification of dopaminergic and serotonergic neurons in the vertebrate CNS.

The early specification of dopaminergic and serotonergic neurons during vertebrate CNS development relies on signals produced by a small number of organizing centers. Recent studies have characterized these early organizing centers, the manner in which they may be established, the inductive signals they produce, and candidate signaling systems that control the later development of the dopaminergic system.

The Aspergillus nidulans gltA gene encoding glutamate synthase is required for ammonium assimilation in the absence of NADP-glutamate dehydrogenase.

Mutants of Aspergillus nidulans lacking NADP-glutamate dehydrogenase activity grow more poorly than wild-type strains on ammonium as a sole nitrogen source. The leaky growth of these mutants is indicative of an alternative pathway of ammonium assimilation and glutamate biosynthesis. We have PCR-amplified a portion of the A.

AnCF, the CCAAT binding complex of Aspergillus nidulans, contains products of the hapB, hapC, and hapE genes and is required for activation by the pathway-specific regulatory gene amdR.

CCAAT binding factors (CBFs) positively regulating the expression of the amdS gene (encoding acetamidase) and two penicillin biosynthesis genes (ipnA and aatA) have been previously found in Aspergillus nidulans. The factors were called AnCF and PENR1, respectively. Deletion of the hapC gene, encoding a protein with significant similarity to Hap3p of Saccharomyces cerevisiae, eliminated both AnCF and PENR1 binding activities.

The facC gene of Aspergillus nidulans encodes an acetate-inducible carnitine acetyltransferase.

Mutations in the facC gene of Aspergillus nidulans result in an inability to use acetate as a sole carbon source. This gene has been cloned by complementation. The proposed translation product of the facC gene has significant similarity to carnitine acetyltransferases (CAT) from other organisms.

Synthesis and preliminary evaluation of MP-2269: a novel, nonaromatic small-molecule blood-pool MR contrast agent.

A nonaromatic, small-molecule, gadolinium(3+)-chelate code named MP-2269 was synthesized and evaluated in animals as a potential MR contrast agent for blood pool. The ligand of MP-2269 was prepared by conjugating a lipophilic, albumin-binding moiety, 4-pentylbicyclo[2.2.

Role of the regulatory gene areA of Aspergillus oryzae in nitrogen metabolism.

The areA gene of Aspergillus oryzae was cloned by cross-hybridization with the Aspergillus nidulans areA gene and was found to encode an 866-amino-acid protein that is very similar to other fungal nitrogen regulatory proteins. The A. oryzae areA gene can complement A.

GFRalpha1 is an essential receptor component for GDNF in the developing nervous system and kidney.

Glial cell line-derived neurotrophic factor (GDNF) is a distant member of the TGFbeta protein family that is essential for neuronal survival and renal morphogenesis. We show that mice who are deficient in the glycosyl-phosphatidyl inositol (GPI) -linked protein GFRalpha1 (GDNFRalpha) display deficits in the kidneys, the enteric nervous system, and spinal motor and sensory neurons that are strikingly similar to those of the GDNF- and Ret-deficient mice. GFRalpha1-deficient dopaminergic and nodose sensory ganglia neurons no longer respond to GDNF or to the structurally related protein neurturin (NTN) but can be rescued when exposed to GDNF or neurturin in the presence of soluble GFRalpha1.

Rhizobium leguminosarum contains a group of genes that appear to code for methyl-accepting chemotaxis proteins.

Methyl-accepting chemotaxis proteins (MCPs) play important roles in the chemotactic response of many bacteria. Oligonucleotide primers designed to amplify the conserved signalling domain of MCPs by PCR were used to identify potential MCP-encoding genes in Rhizobium leguminosarum. Using a PCR-derived probe created from these primers a genomic library of R.

Rhizobium tropici teu genes involved in specific uptake of Phaseolus vulgaris bean-exudate compounds.

Rhizobium tropici nodulates and fixes nitrogen in bean. In the R. tropici strain CFN299 we identified and characterized teu genes (tropici exudate uptake) induced by bean root exudates, localized by insertion of a promoter-less Tn5-gusA1 transposon.

Feasibility of population based screening in Ireland.

Population registers have formed the basis for computerised call/recall registers for screening programmes in many countries and have been important in achieving high uptakes in targeted populations. The absence of a population register for the ECCLES (European Campaign against Cancer, Localisation, Evaluation & Screening) Breast Screening Project necessitated the development of a special register of women in the target age group. The data sources used to build the project register were the Eastern Health Board and North Eastern Health Board General Medical Services database, Voluntary Health Insurance data and self-registration with the project.

Neurturin exerts potent actions on survival and function of midbrain dopaminergic neurons.

Glial cell line-derived neurotrophic factor (GDNF) exhibits potent effects on survival and function of midbrain dopaminergic (DA) neurons in a variety of models. Although other growth factors expressed in the vicinity of developing DA neurons have been reported to support survival of DA neurons in vitro, to date none of these factors duplicate the potent and selective actions of GDNF in vivo. We report here that neurturin (NTN), a homolog of GDNF, is expressed in the nigrostriatal system, and that NTN exerts potent effects on survival and function of midbrain DA neurons.

FGF and Shh signals control dopaminergic and serotonergic cell fate in the anterior neural plate.

During development, distinct classes of neurons are specified in precise locations along the dorso-ventral and anterior-posterior axes of the neural tube. We provide evidence that intersections of Shh, which is expressed along the ventral neural tube, and FGF8, which is locally produced at the mid/hindbrain boundary and in the rostral forebrain, create induction sites for dopaminergic neurons in the midbrain and forebrain. The same intersection, when preceded by a third signal, FGF4, which is expressed in the primitive streak, defines an inductive center for hindbrain 5-HT neurons.

FacB, the Aspergillus nidulans activator of acetate utilization genes, binds dissimilar DNA sequences.

The facB gene is required for acetate induction of acetamidase (amdS) and the acetate utilization enzymes acetyl-CoA synthase (facA), isocitrate lyase (acuD) and malate synthase (acuE) in Aspergillus nidulans. The facB gene encodes a transcriptional activator with a GAL4-type Zn(II)2Cys6 zinc binuclear cluster DNA-binding domain which is shown to be required for DNA binding. In vitro DNA-binding sites for FacB in the 5' regions of the amdS, facA, acuD and acuE genes have been identified.

Expression of a Bacillus thuringiensis delta-endotoxin gene by Bacillus pumilus.

The delta-endotoxin genes from Bacillus thuringiensis were introduced into a rhizosphere-inhabiting Bacillus pumilus isolate to create a delta-endotoxin expression and delivery system for subterranean feeding insects such as the larvae of pale western cutworm (Agrotis orthogonia Morrison (Lepidoptera: Noctuidae)). Preliminary experiments indicated that Bacillus thuringiensis subsp. kurstaki cultures were toxic to pale western cutworm larvae.

Women in New York City's Medicaid program: a report on satisfaction, access, and use.

This article analyzes the experiences of women in New York City's Medicaid program regarding their satisfaction with, access to, and use of medical care during an early phase of a managed care enrollment initiative. Data for this study are from a 1994 survey of New York City Medicaid beneficiaries (1,221 women) as well as from focus group discussions. Differences in reported satisfaction levels, access, and use between managed care enrollees and conventional Medicaid beneficiaries are examined, as are differences between women in fair and poor health and those in excellent, very good, and good health.

Decreased symbiotic effectiveness of Rhizobium leguminosarum strains carrying plasmid RP4.

The presence of derivatives of the broad host range plasmid RP4 in strains of Rhizobium leguminosarum biovar viciae severely inhibited nitrogen fixation by these strains in nodules on cultivars of pea (Pisum sativum). The strains formed small white nodules. Yield and total nitrogen values were comparable with those obtained for plants inoculated with a non-nodulating mutant.

Characterization of the Aspergillus nidulans nmrA gene involved in nitrogen metabolite repression.

The gene nmrA of Aspergillus nidulans has been isolated and found to be a homolog of the Neurospora crassa gene nmr-1, involved in nitrogen metabolite repression. Deletion of nmrA results in partial derepression of activities subject to nitrogen repression similar to phenotypes observed for certain mutations in the positively acting areA gene.

The Aspergillus nidulans CCAAT-binding factor AnCP/AnCF is a heteromeric protein analogous to the HAP complex of Saccharomyces cerevisiae.

The Aspergillus nidulans hapC gene was expressed as a fusion protein with MalE or glutathione-S-transferase (GST) in Escherichia coli, and used for the purification of HapC and the preparation of anti-HapC antiserum. The CCAAT-binding factor AnCP/AnCF contains a component with an approximate molecular mass of 32 kDa that cross-reacts with the antibody. The MalE-HapC fusion protein was able to replace authentic HapC in AnCP when incubated under appropriate conditions.

Persephin, a novel neurotrophic factor related to GDNF and neurturin.

A novel neurotrophic factor named Persephin that is approximately 40% identical to glial cell line-derived neurotrophic factor (GDNF) and neurturin (NTN) has been identified using degenerate PCR. Persephin, like GDNF and NTN, promotes the survival of ventral midbrain dopaminergic neurons in culture and prevents their degeneration after 6-hydroxydopamine treatment in vivo. Persephin also supports the survival of motor neurons in culture and in vivo after sciatic nerve axotomy and, like GDNF, promotes ureteric bud branching.

The penicillin regulator PENR1 of Aspergillus nidulans is a HAP-like transcriptional complex.

In Aspergillus nidulans, a DNA-binding complex, PENR1, was shown to bind to two CCAAT-box-containing DNA elements located in the promoter regions of the bidirectionally oriented penicillin biosynthesis genes acvA and ipnA, and of the aat promoter. Here, partial purification of PENR1 and western blotting using anti-HAPC sera indicated that the previously identified HAPC protein, which was suggested to be part of the CCAAT-binding complex AnCF, is also part of PENR1. This was confirmed by band shift assays using protein extracts of a delta hapC strain which exhibited no PENR1 DNA-binding activity.