A multi-country Salmonella Enteritidis phage type 14b outbreak associated with eggs from a German producer: 'near real-time' application of whole genome sequencing and food chain investigations, United Kingdom, May to September 2014.

We report an outbreak of Salmonella Enteritidis phage type 14b (PT14b) in the United Kingdom (UK) between May and September 2014 where Public Health England launched an investigation to identify the source of infection and implement control measures. During the same period, outbreaks caused by a Salmonella Enteritidis strain with a specific multilocus variable-number tandem repeat analysis (MLVA) profile occurred in other European Union Member States. Isolates from a number of persons affected by the UK outbreak, who had initially been tested by MLVA also shared this particular profile. Cases were defined as any person infected with S. Enteritidis PT14b, resident in England or Wales and without history of travel outside of this geographical area during the incubation period, reported from 1 June 2014 onwards, with a MLVA profile of 2­11­9-7­4-3­2-8­9 or a single locus variant thereof. In total, 287 cases met the definition. Food traceback investigations in the UK and other affected European countries linked the outbreaks to chicken eggs from a German company. We undertook whole genome sequencing of isolates from UK and European cases, implicated UK premises, and German eggs: isolates were highly similar. Combined with food traceback information, this confirmed that the UK outbreak was also linked to a German producer.

An outbreak of hepatitis A affecting a nursery school and a primary school.

Between March and June 2008, 12 cases of hepatitis A were notified in Winchester. Cases were from a primary school and a nursery school with no direct linkage. Hepatitis A virus (HAV) RNA sequenced from nine cases confirmed the strain in both schools to be identical. The outbreak could have affected three other schools and a maternity unit and was controlled by immunization and screening of neonates in the maternity unit by dried blood spots. No neonates were infected and no further cases were reported until 5 months later when the index case's mother became infected with same strain of virus associated with the outbreak despite vaccination. Neither the source of the outbreak or the subsequent infection of the index case's mother was identified; however, with the timing of the cases continued transmission in the community by children with asymptomatic infection or a recurrent source cannot be ruled out.

Evaluation of surgical experience and the use of an osteotomy guide on the apical angle of an Austin osteotomy.

BACKGROUND: Distal osteotomies of the first metatarsal are commonly used to correct hallux valgus deformities. Of the distal osteotomies, the Austin osteotomy is popular among foot surgeons on an international level. The precision of the osteotomy is important to achieve a congruous osteotomy. OBJECTIVES: The purpose of this study was to examine the effects of experience and technique on creating a precise Austin osteotomy. METHOD: Three individuals with varying levels of experience (student, resident and podiatric physician) created Austin osteotomies in metatarsal sawbones, using three different techniques (freehand, guide wire and osteotomy guide). The medial and lateral apical angles were measured, and the mean, standard deviation, and range of the angles were calculated. The differences between medial and lateral angles were also calculated. RESULTS: The results indicated that the mean and range of the angles varied considerably with the freehand and guide wire techniques at all experience levels. The angles were accurate and consistent for all experience levels; however, when an osteotomy guide was used. The use of an osteotomy guide also noticeably reduced the number of divergent and convergent osteotomies. CONCLUSIONS: The use of an osteotomy guide consistently resulted in a more precise Austin osteotomy for all experience levels.

The place of the thalamus in frontal cortical-basal ganglia circuits.

The thalamus has long been thought to convey subcortical information to the cortex. Indeed, models of basal ganglia function attribute the primary role for the thalamus to a simple relay of information processed in the basal ganglia to the cortex. The thalamic nuclear groups that are associated primarily with this function are the ventral anterior and ventral lateral nuclei and the mediodorsal thalamic nucleus. However, recent studies have shown that the corticothalamic projection is important for the dynamics of the thalamocortical processing. Furthermore, the relay nuclei that carry basal ganglia output to the cortex have recently been shown to project back to the basal ganglia directly. These two recent developments indicate a more dynamic role for the thalamus in basal ganglia information processing than a passive relay.

Organization of thalamostriatal terminals from the ventral motor nuclei in the macaque.

This study examines the organization of thalamostriatal projections from ventral tier nuclei that relay basal ganglia output to the frontal cortex. Although previous thalamostriatal studies emphasize projections from the intralaminar nuclei, studies in primates show a substantial projection from the ventral anterior (VA) and ventral lateral (VL) nuclei. These nuclei make up the main efferent projection from the basal ganglia to frontal cortical areas, including primary motor, supplementary, premotor, and cingulate motor areas. Functionally related motor areas of the frontal cortex and VA/VL have convergent projections to specific regions of the dorsal striatum. The distribution of VA/VL terminals within the striatum is crucial to understanding their relationship to motor cortical afferents. We placed anterograde tracer injections into discrete VA/VL thalamic areas. VA/VL thalamostriatal projections terminate in broad, rostrocaudal regions of the dorsal striatum, corresponding to regions innervated by functionally related cortical motor areas. The pars oralis division of VL projects primarily to the dorsolateral, postcommissural putamen, whereas the parvicellular VA targets more medial and rostral putamen regions, and the magnocellular division of VA targets the dorsal head of the caudate nucleus. Whereas these results demonstrate a general functional topography, specific VA/VL projections overlap extensively, suggesting that functionally distinct VA/VL projections may also converge in dorsal striatal areas. Within striatal territories, VA/VL projections terminate in a patchy, nonhomogeneous manner, indicating another level of complexity. Moreover, terminal fields contain both terminal clusters and scattered, long, unbranched fibers with many varicosities. These fiber morphologies resemble those from the cortex and raise the possibility that VA/VL thalamostriatal projections neurons have divergent connectional features.

Convergent inputs from thalamic motor nuclei and frontal cortical areas to the dorsal striatum in the primate.

Current models of basal ganglia circuitry primarily associate the ventral thalamic nuclei with relaying basal ganglia output to the frontal cortex. However, some studies have demonstrated projections from the ventral anterior (VA) and ventral lateral (VL) thalamic nuclei to the striatum, suggesting that these nuclei directly modulate the striatum. VA/VL nuclei have specific connections with primary, supplementary, premotor, and cingulate motor cortices indicating their involvement in motor function. These areas mediate different aspects of motor control such as movement execution, motor learning, and sensorimotor integration. Increasing evidence indicates that functionally related motor areas have convergent projections to the dorsal striatum, suggesting that integration of different aspects of motor control occur at the level of the striatum. This study examines the organization of VA/VL thalamic inputs to the dorsal "motor" striatum to determine how this afferent projection is organized with respect to corticostriatal afferents from motor, premotor, and cingulate motor areas. Motor cortical projections to specific dorsal striatal regions arose from multiple areas, including components from primary motor, premotor, supplementary, and cingulate motor areas. Diverse motor cortical projections to a given dorsal striatal region indicated convergence of functionally related corticostriatal motor pathways. Most dorsal striatal sites received dense thalamic inputs from the VL pars oralis nucleus. Additional thalamostriatal projections arose from VA, VL pars caudalis, and ventral posterior lateral pars oralis nuclei and Olszewski's Area X. Our results provide evidence for convergent striatal projections from interconnected ventral thalamic and cortical motor areas, suggesting that these afferents modulate the same striatal output circuits.

Striatonigrostriatal pathways in primates form an ascending spiral from the shell to the dorsolateral striatum.

Clinical manifestations in diseases affecting the dopamine system include deficits in emotional, cognitive, and motor function. Although the parallel organization of specific corticostriatal pathways is well documented, mechanisms by which dopamine might integrate information across different cortical/basal ganglia circuits are less well understood. We analyzed a collection of retrograde and anterograde tracing studies to understand how the striatonigrostriatal (SNS) subcircuit directs information flow between ventromedial (limbic), central (associative), and dorsolateral (motor) striatal regions. When viewed as a whole, the ventromedial striatum projects to a wide range of the dopamine cells and receives a relatively small dopamine input. In contrast, the dorsolateral striatum (DLS) receives input from a broad expanse of dopamine cells and has a confined input to the substantia nigra (SN). The central striatum (CS) receives input from and projects to a relatively wide range of the SN. The SNS projection from each striatal region contains three substantia nigra components: a dorsal group of nigrostriatal projecting cells, a central region containing both nigrostriatal projecting cells and its reciprocal striatonigral terminal fields, and a ventral region that receives a specific striatonigral projection but does not contain its reciprocal nigrostriatal projection. Examination of results from multiple tracing experiments simultaneously demonstrates an interface between different striatal regions via the midbrain dopamine cells that forms an ascending spiral between regions. The shell influences the core, the core influences the central striatum, and the central striatum influences the dorsolateral striatum. This anatomical arrangement creates a hierarchy of information flow and provides an anatomical basis for the limbic/cognitive/motor interface via the ventral midbrain.

The concept of the ventral striatum in nonhuman primates.

The concept of the ventral striatum was first put forth by Heimer and Wilson to describe the extension of basal ganglia elements into the olfactory tubercle. The ventral striatum includes the conventional nucleus accumbens, which has been closely associated with reward and motivation. This paper uses the afferent connections to the ventral striatum to define this region in monkeys. Furthermore the shell and core subterritories are discussed with respect to their histochemistry and specific connections.

Genetic approaches to the detection of contaminants in Escherichia coli fermentations.

In facilities which cultivate more than one rDNA organism, contamination by the same species is difficult to detect. Since the same species may be producing a different product in an adjacent fermentor or in the same vessel in a subsequent procedure, the possibility of cross-product contamination must be considered. Here we describe a simple, sensitive, and reliable technique for the detection of same-species contamination. The assay uses negative genetic markers such as the inability to use a carbohydrate, e.g., ribose. When the facility is managed to use the ribose marker for only one product, this culture can be plated on ribose minimal medium to allow rapid and sensitive detection of contaminants. If the facility is used for several rDNA products, multiple carbohydrate markers per strain can be used so that a limited number of markers can differentiate among larger host collections. The approach was developed and tested using Escherichia coli as the host organism. If hosts with auxotrophies, e.g., for amino acids, are used in the facility, the plate medium can be supplemented. When this technique is combined with existing methods for detecting different species and bacteriophage contamination, all three classes of biological contamination can be detected.

Insular cortical projections to functional regions of the striatum correlate with cortical cytoarchitectonic organization in the primate.

We examined the striatal projections from different cytoarchitectonic regions of the insular cortex using anterograde and retrograde techniques. The shell and medial ventral striatum receive inputs primarily from the agranular and ventral dysgranular insula. The central ventral striatum receives inputs primarily from the dorsal agranular and dysgranular insula. Projections to the central ventral striatum originate from more posterior and dorsal insular regions than projections to the medial ventral striatum. The dorsolateral striatum receives projections primarily from the dorsal dysgranular and granular insula. These results show that cytoarchitectonically less differentiated (agranular) insular regions project to the ventromedial "limbic" part of the ventral striatum, whereas more differentiated (granular) insular regions project to the dorsolateral "sensorimotor" part of the striatum. The finding that the ventral "limbic" striatum receives inputs from less differentiated regions of the insula is consistent with the general principle that less differentiated cortical regions project primarily to the "limbic" striatum. Functionally, the ventral striatum receives insular projections primarily related to integrating feeding behavior with rewards and memory, whereas the dorsolateral striatum receives insular inputs related to the somatosensation. Information regarding food acquisition in the insula may be sent to the intermediate area of the striatum.

Control of islet intercellular adhesion molecule-1 expression by interferon-alpha and hypoxia.

The ability of interferon-alpha (IFN-alpha) to induce the adhesion molecules that characterize the islets of patients with type I diabetes has been investigated. We have found that all tested recombinant IFN-as will induce major histocompatibility complex (MHC) class I on arterial endothelial cells. Some but not all IFN-as will induce intercellular adhesion molecule-1 (ICAM-1). However, there is only a transient and modest increase in VCAM on arterial endothelial cells. IFN-alpha has very little effect on endothelial MHC class II expression but will induce these proteins on monocytes. Thus, there is a close concordance between the biological actions of IFN-alpha and the appearance of those adhesion molecules induced in the islets of patients with type I diabetes. IFN-alpha is also produced in normal human islets during short-term cultures, probably as a result of the ischemia present at the center of the islet. This induction of IFN-alpha by hypoxia may explain the previously reported spontaneous induction of ICAM-1 in human islets and may also be a contributing factor to the failure of islet grafts.

Organization of thalamic projections to the ventral striatum in the primate.

Although thalamic projections to the dorsal striatum are well described in primates and other species, little is known about thalamic projections to the ventral or "limbic" striatum in the primate. This study explores the organization of the thalamic projections to the ventral striatum in the primate brain by means of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) and Lucifer yellow (LY) retrograde tracer techniques. In addition, because functional and connective differences have been described for the core and shell components of the nucleus accumbens in the rat and are thought to be similar in the primate, this study also explores whether these regions of the nucleus accumbens can be distinguished by their thalamic input. Tracer injections are placed in different portions of the ventral striatum, including the medial and lateral regions of the ventral striatum; the central region of the ventral striatum, including the dorsal part of the core of the nucleus accumbens; and the shell region of the nucleus accumbens. Retrogradely labeled neurons are located mainly in the midline nuclear group (anterior and posterior paraventricular, paratenial, rhomboid, and reuniens thalamic nuclei) and in the parafascicular thalamic nucleus. Additional labeled cells are found in other portions of the intralaminar nuclear group as well as in other thalamic nuclei in the ventral, anterior, medial, lateral, and posterior thalamic nuclear groups. The distribution of labeled cells varies depending on the area of the ventral striatum injected. All regions of the ventral striatum receive strong projections from the midline thalamic nuclei and from the parafascicular nucleus. In addition, the medial region of the ventral striatum receives numerous projections from the central superior lateral nucleus, the magnocellular subdivision of the ventral anterior nucleus, and parts of the mediodorsal nucleus. After injection into the lateral region of the ventral striatum, few labeled neurons are seen scattered in nuclei of the intralaminar and ventral thalamic groups and occasional labeled cells in the mediodorsal nucleus. The central region of the ventral striatum, including the dorsal part of the core of the nucleus accumbens, receives a limited projection from the midline thalamic, predominantly from the rhomboid nucleus. It receives much smaller projections from the central medial nucleus and the ventral, anterior, and medial thalamic groups. The shell of the nucleus accumbens receives the most limited projection from the thalamus and is innervated almost exclusively by the midline thalamic nuclei and the central medial and parafascicular nuclei. The shell is distinguished from the rest of the ventral striatum in that it receives the fewest projections from the ventral, anterior, medial, and lateral thalamic nuclei.

Processing of iridoid glycoside antirrinoside fromMaurandya antirrhiniflora (Scrophulariaceae) byMeris paradoxa (Geometridae) andLepipolys species (Noctuidae).

The iridoid glycoside antirrinoside was found to be sequestered by highly aposematic larvae of the geometrid mothMeris paradoxa and two noctuid mothLepipolys species feeding onMaurandya antirrhiniflora (Scrophulariaceae), a natural food plant from southern Arizona. The antirrinoside content of leaves and petioles being consumed, eariy-instar larvae, late-instar larvae, larval frass, regurgitant, reflex-bleeding emission (Meris paradoxa), cocoons, pupae, meconium emitted upon eclosion, and adult moths was determined. Larvae, other than the earliest instars, did not excrete antirrinoside in the frass, but sequestered it in amounts of 3-11 % of the dry weight. Small amounts of antirrinoside remained in various pupal or cocoon parts and some was emitted in the meconium upon eclosion. The total antirrinoside accounted for was, however, considerably below that expected based upon the remarkably high 20% content of the leaves and petioles being consumed. The adult cryptic moths of both species contained little or no antirrinoside. This is the first report of a natural food plant and larval stages forM. paradoxa and a previously undescribedLepipolys species. It is also the first report of antirrinoside sequestration and utilization by insects.

The human growth hormone receptor. Secretion from Escherichia coli and disulfide bonding pattern of the extracellular binding domain.

A gene fragment encoding the extracellular domain of the human growth hormone (hGH) receptor from liver was cloned into a plasmid under control of the Escherichia coli alkaline phosphatase promoter and the heat-stable enterotoxin (StII) signal peptide sequence. Strains of E. coli expressing properly folded hGH binding protein were identified by blotting colonies with 125I-hGH. The E. coli strain capable of highest expression (KS330) secreted 10 to 20 mg/liter of culture of properly processed and folded hGH receptor fragment into the periplasmic space. The protein was purified to near homogeneity in 70 to 80% yield (in tens of milligram amounts) using ammonium sulfate precipitation, hGH affinity chromatography, and gel filtration. The unglycosylated extracellular domain of the hGH receptor has virtually identical binding properties compared to its natural glycosylated counterpart isolated from human serum, suggesting glycosylation is not important for binding of hGH. The extracellular binding domain codes for 7 cysteines, and we show that six of them form three disulfide bonds. Peptide mapping studies show these disulfides are paired sequentially to produce short loops (10-15 residues long) as follows: Cys38-Cys48, Cys83-Cys94, and Cys108-Cys122. Cys241 is unpaired, and mutagenic analysis shows that the extreme carboxyl end of the receptor fragment (including Cys241) is not essential for folding or binding of the protein to hGH. High level expression of this receptor binding domain and its homologs in E. coli will greatly facilitate their detailed biophysical and structural analysis.

Iridoid glycoside sequestration by two aposematicPenstemon-feeding geometrid larvae.

The iridoid glycoside catalpol was found to be sequestered by larvae ofMeris alticola feeding onPenstemon virgatus and by larvae ofNeoterpes graefiaria which utilizeP. barbatus. The strikingly similar larval patterns of these two ennomine geometrids were previously considered to be disruptive, but predator-based Mullerian mimicry is equally likely to be involved. The cryptic adult moths generally contain only small amounts of catalpol, having left most of the bitter iridoid in the pupal case and in the meconium excreted after eclosion. OneNeoterpes female did contain considerable catalpol in the abdomen, presumably in the eggs.

Nitrogen regulatory locus "glnR" of enteric bacteria is composed of cistrons ntrB and ntrC: identification of their protein products.

The nitrogen regulatory locus "glnR" of Escherichia coli and Salmonella typhimurium is composed of two cistrons, which we propose to call ntrB and ntrC (nitrogen regulation B and C). Frameshift mutations in ntrB and ntrC were isolated on a lambda phage that carries the E. coli ntrB and ntrC genes and the closely linked glnA gene, the structural gene encoding glutamine synthetase [L-glutamate:ammonia ligase (ADP-forming), EC 6.3.1.2]; mutations were selected as suppressors of glnF (which we propose to rename ntrA), a selection used previously to isolate glnR mutations. Phage DNA from one mutant (ntrB) failed to direct synthesis of a 36-kilodalton (kDal) protein whose synthesis was directed by DNA from the parent phage (ntrB+) in a coupled in vitro transcription/translation system. DNA from three other mutants (ntrC) failed to direct synthesis of a 54-kDal protein; DNA from two of these mutants instead directed synthesis of smaller proteins, 53 and 50 kDal, respectively. In all four cases, DNA from frameshift revertants directed synthesis of both the 36-kDal and 54-kDal proteins. These results suggested that ntrB and ntrC were separate genes which encoded 36-kDal and 54-kDal protein products, respectively. Frameshift mutations in ntrB and ntrC complemented each other with regard to regulation of glnA expression in vivo and growth on arginine as nitrogen source, another nitrogen-controlled phenotype; this confirmed that ntrB and ntrC are separate cistrons that encode diffusible products. The ntrB and ntrC genes were also defined in S. typhimurium. Studies of mutant strains provided information on the roles of the ntrB and ntrC products in activation and repression of glnA expression and raised the possibility that these products function as a protein complex in regulating expression of nitrogen-controlled genes.

Nitrogen control in Salmonella: regulation by the glnR and glnF gene products.

The product of the glnR gene is required for nitrogen regulation of the synthesis of glutamine synthesis (Gln synthetase) [L-glutamate:ammonia ligase (ADP-forming), EC 6.3.1.2] and two periplasmic transport proteins that are subject to nitrogen control in Salmonella. Strains with mutations to loss of function of the glnR product [e.g., a strain with a Tn10 insertion or one with an ICR-induced (frameshift) mutation in glnR] have about 3% as much Gln synthetase as a fully derepressed wild-type strain and are unable to increase synthesis of this enzyme or periplasmic transport proteins in response to nitrogen limitation. The structural gene for Gln synthetase, glnA, and those for the periplasmic transport proteins are unlinked on the chromosome; thus, glnR appears to encode a diffusible positive regulatory element. Consistent with this, the mutant glnR allele is recessive to the wild-type allele with regard to expression of glnA (synthesis of Gln synthetase). Although glnR is closely linked to glnA, strains with mutations to complete loss of function of the glnR product can be distinguished from glnA strains by their ability to produce detectable Gln synthetase and to grow in the absence of glutamine. To demonstrate unequivocally that glnR is distinct from glnA, we have purified and characterized Gln synthetase from a strain with a Tn10 insertion in glnR. Because the properties of Gln synthetase from the insertion mutant, most importantly the carboxyl-terminal sequence of amino acids, are the same as those of synthetase from wild type, the Tn10 insertion cannot be in glnA (if it were, the carboxyl terminus of Gln synthetase would have to be altered); therefore we conclude that the Tn10 insertion is in a regulatory gene, glnR, which is distinct from glnA. A model for the function of the glnR product together with the previously defined glnF product in mediating nitrogen control is discussed.

Nitrogen control of Salmonella typhimurium: co-regulation of synthesis of glutamine synthetase and amino acid transport systems.

Nitrogen control in Salmonella typhimurium is not limited to glutamine synthetase but affects, in addition, transport systems for histidine, glutamine, lysine-arginine-ornithine, and glutamate-aspartate. Synthesis of both glutamine synthetase and transport proteins is elevated by limitation of nitrogen in the growth medium or as a result of nitrogen (N)-regulatory mutations. Increases in the amounts of these proteins were demonstrated by direct measurements of their activities, by immunological techniques, and by visual inspection of cell fractions after gel electrophoresis. The N-regulatory mutations are closely linked on the chromosome to the structural gene for glutamine synthetase, glnA: we discuss the possibility that they lie in a regulatory gene, glnR, which is distinct from glnA. Increases in amino acid transport in N-regulatory mutant strains were indicated by increased activity in direct transport assays, improved growth on substrates of the transport systems, and increased sensitivity to inhibitory analogs that are trnasported by these systems. Mutations to loss of function of individual transport components (hisJ, hisP, glnH, argT) were introduced into N-regulatory mutant strains to determine the roles of these components in the phenotype and transport behavior of the strains. The structural gene for the periplasmic glutamine-binding protein, glnH, was identified, as was a gene argT that probably encodes the structure of the lysine-arginine-ornithine-binding protein. Genes encoding the structures of the histidine- and glutamine-binding proteins are not linked to glnA or to each other by P22-mediated transduction; thus, nitrogen control is exerted on several unlinked genes.