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1.
Eur J Emerg Med ; 30(6): 402-407, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37883238

ABSTRACT

Increasing indications, reports and studies demonstrate that threats from the deliberate use of chemical weapons remain high and are evolving. One of the deadliest classes of chemical weapons are the organophosphorus nerve agents. It is now clear that both state and non-state actors have the ability to deploy and use these types of weapons against individuals and the wider civilian population posing a real and significant threat. The objective of this article is to provide an overview of the issues impacting on a timely critical response to the accidental or deliberate release of Organophosphorus Nerve Agents in order to enhance the understanding of their effects and provide guidance on how first responders might better treat themselves or victims of exposure through a discussion of available evidence and best practices for rapid skin decontamination. The article also examines use of the current nomenclature of 'wet' and 'dry' to describe different forms of decontamination. One of the key conclusions of this article is that adequate preparedness is essential to ensuring that responders are trained to understand the threat posed by Organophosphorus Nerve Agents as well as how to approach a contaminated environment. A key aspect to achieving this will be to ensure that generic medical countermeasures are forward-deployed and available, preferably within minutes of a contamination and that first responders know how to use them.


Subject(s)
Nerve Agents , Organophosphorus Compounds , Humans , Decontamination , Nerve Agents/toxicity
2.
BMJ Qual Saf ; 28(6): 449-458, 2019 06.
Article in English | MEDLINE | ID: mdl-30877149

ABSTRACT

BACKGROUND: Reducing costs while increasing or maintaining quality is crucial to delivering high value care. OBJECTIVE: To assess the impact of a hospital value-based management programme on cost and quality. DESIGN: Time series analysis of non-psychiatric, non-rehabilitation, non-newborn patients discharged between 1 September 2011 and 31 December 2017 from a US urban, academic medical centre. INTERVENTION: NYU Langone Health instituted an institution-wide programme in April 2014 to increase value of healthcare, defined as health outcomes achieved per dollar spent. Key features included joint clinical and operational leadership; granular and transparent cost accounting; dedicated project support staff; information technology support; and a departmental shared savings programme. MEASUREMENTS: Change in variable direct costs; secondary outcomes included changes in length of stay, readmission and in-hospital mortality. RESULTS: The programme chartered 74 projects targeting opportunities in supply chain management (eg, surgical trays), operational efficiency (eg, discharge optimisation), care of outlier patients (eg, those at end of life) and resource utilisation (eg, blood management). The study cohort included 160 434 hospitalisations. Adjusted variable costs decreased 7.7% over the study period. Admissions with medical diagnosis related groups (DRG) declined an average 0.20% per month relative to baseline. Admissions with surgical DRGs had an early increase in costs of 2.7% followed by 0.37% decrease in costs per month. Mean expense per hospitalisation improved from 13% above median for teaching hospitals to 2% above median. Length of stay decreased by 0.25% per month relative to prior trends (95% CI -0.34 to 0.17): approximately half a day by the end of the study period. There were no significant changes in 30-day same-hospital readmission or in-hospital mortality. Estimated institutional savings after intervention costs were approximately $53.9 million. LIMITATIONS: Observational analysis. CONCLUSION: A systematic programme to increase healthcare value by lowering the cost of care without compromising quality is achievable and sustainable over several years.


Subject(s)
Academic Medical Centers/economics , Cost-Benefit Analysis , Direct Service Costs/statistics & numerical data , Efficiency, Organizational/economics , Female , Health Services Research , Hospital Mortality , Humans , Length of Stay/economics , Length of Stay/statistics & numerical data , Male , Middle Aged , New York City , Patient Readmission/economics , Patient Readmission/statistics & numerical data , Urban Health
3.
Plant Physiol ; 169(3): 2166-86, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26417006

ABSTRACT

In the model plant Arabidopsis (Arabidopsis thaliana), endogenous and environmental signals acting on the shoot apical meristem cause acquisition of inflorescence meristem fate. This results in changed patterns of aerial development seen as the transition from making leaves to the production of flowers separated by elongated internodes. Two related BEL1-like homeobox genes, PENNYWISE (PNY) and POUND-FOOLISH (PNF), fulfill this transition. Loss of function of these genes impairs stem cell maintenance and blocks internode elongation and flowering. We show here that pny pnf apices misexpress lateral organ boundary genes BLADE-ON-PETIOLE1/2 (BOP1/2) and KNOTTED-LIKE FROM ARABIDOPSIS THALIANA6 (KNAT6) together with ARABIDOPSIS THALIANA HOMEOBOX GENE1 (ATH1). Inactivation of genes in this module fully rescues pny pnf defects. We further show that BOP1 directly activates ATH1, whereas activation of KNAT6 is indirect. The pny pnf restoration correlates with renewed accumulation of transcripts conferring floral meristem identity, including FD, SQUAMOSA PROMOTER-BINDING PROTEIN LIKE genes, LEAFY, and APETALA1. To gain insight into how this module blocks flowering, we analyzed the transcriptome of BOP1-overexpressing plants. Our data suggest a central role for the microRNA156-SQUAMOSA PROMOTER BINDING PROTEIN-LIKE-microRNA172 module in integrating stress signals conferred in part by promotion of jasmonic acid biosynthesis. These data reveal a potential mechanism by which repression of lateral organ boundary genes by PNY-PNF is essential for flowering.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/genetics , Gene Expression Regulation, Plant , Homeodomain Proteins/metabolism , Repressor Proteins/metabolism , Arabidopsis/growth & development , Arabidopsis/physiology , Arabidopsis Proteins/genetics , Cyclopentanes/metabolism , Flowers/genetics , Flowers/growth & development , Flowers/physiology , Homeodomain Proteins/genetics , Meristem/genetics , Meristem/growth & development , Meristem/physiology , MicroRNAs/genetics , Mutation , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Oxylipins/metabolism , Plant Growth Regulators/metabolism , Repressor Proteins/genetics , Reproduction , Signal Transduction
4.
J Hosp Med ; 9(4): 210-4, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24446232

ABSTRACT

BACKGROUND: Late afternoon hospital discharges are thought to contribute to admission bottlenecks, overcrowding, and increased length of stay (LOS). In January 2012, the discharge before noon (DBN) percentage on 2 medical units was 7%, below the organizational goal of 30%. OBJECTIVE: To sustainably achieve a DBN rate of 30% and to evaluate the effect of this intervention on observed-to-expected (O/E) LOS and 30-day readmission rate. DESIGN: Pre-/post-intervention retrospective analysis. SETTING: Two acute care inpatient medical units in an urban, academic medical center. PATIENTS: All inpatients discharged from the units. INTERVENTION: All staff helped create a checklist of daily responsibilities at a DBN kickoff event. We initiated afternoon interdisciplinary rounds to identify next-day DBNs and created a website for enhanced communication. We provided daily feedback on the DBN percentage, rewards for success, and real-time opportunities for case review. MEASUREMENTS: Calendar month DBN percentage, O/E LOS, and 30-day readmission rate. RESULTS: The DBN percentage increased from 11% in the 8-month baseline period to an average of 38% over the 13-month intervention (P = 0.0002). The average discharge time moved 1 hour and 31 minutes earlier in the day. The O/E LOS declined from 1.06 to 0.96 (P = 0.0001), and the 30-day readmission rate declined from 14.3% to 13.1% (P = 0.1902). CONCLUSIONS: Our study demonstrates that increased DBN is an achievable and sustainable goal for hospitals. Future work will allow for better understanding of the full effects of such an intervention on patient outcomes and hospital metrics.


Subject(s)
Academic Medical Centers/organization & administration , Organizational Objectives , Patient Discharge , Academic Medical Centers/statistics & numerical data , Checklist , Humans , Length of Stay/statistics & numerical data , Motivation , Patient Readmission/statistics & numerical data , Process Assessment, Health Care , Retrospective Studies , Time Factors
5.
Methods Mol Biol ; 1062: 301-15, 2014.
Article in English | MEDLINE | ID: mdl-24057374

ABSTRACT

Next-generation sequencing platforms have made it possible to very rapidly map genetic mutations in Arabidopsis using whole-genome resequencing against pooled members of an F2 mapping population. In the case of recessive mutations, all individuals expressing the phenotype will be homozygous for the mutant genome at the locus responsible for the phenotype, while all other loci segregate roughly equally for both parental lines due to recombination. Importantly, genomic regions flanking the recessive mutation will be in linkage disequilibrium and therefore also be homozygous due to genetic hitchhiking. This information can be exploited to quickly and effectively identify the causal mutation. To this end, sequence data generated from members of the pooled population exhibiting the mutant phenotype are first aligned to the reference genome. Polymorphisms between the mutant and mapping line are then identified and used to determine the homozygous, nonrecombinant region harboring the mutation. Polymorphisms in the identified region are filtered to provide a short list of markers potentially responsible for the phenotype of interest, which is followed by validation at the bench. Although the focus of recent studies has been on the mapping of point mutations exhibiting recessive phenotypes, the techniques employed can be extended to incorporate more complicated scenarios such as dominant mutations and those caused by insertions or deletions in genomic sequence. This chapter describes detailed procedures for performing next-generation mapping against an Arabidopsis mutant and discusses how different mutations might be approached.


Subject(s)
Arabidopsis/genetics , Chromosome Mapping/methods , DNA Mutational Analysis , Genetic Association Studies , Genome, Plant , Haplotypes , High-Throughput Nucleotide Sequencing , Phenotype , Sequence Alignment , Software
6.
Plant Cell Environ ; 36(1): 68-86, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22681544

ABSTRACT

Excised plant tissues (explants) can regenerate new shoot apical meristems in vitro, but regeneration rates can be inexplicably variable. Light affects rates of shoot regeneration, but the underlying mechanisms are poorly understood. Here, excised Arabidopsis cotyledons were dark-light shifted to define the timing of explant light sensitivity. Mutants and pharmacological agents were employed to uncover underlying physiological and genetic mechanisms. Unexpectedly, explants were most light sensitive during the initial hours post-excision with respect to shoot regeneration. Only ∼100 µmol m(-2 ) s(-1) of fluorescent light was sufficient to induce reactive oxygen species (ROS) accumulation in new explants. By 48 h post-excision, induction of ROS, or quenching of ROS by xanthophylls, increased or decreased shoot regeneration, respectively. Phytochrome A-mediated signalling suppressed light inhibition of regeneration. Early exposure to blue/UV-A wavelengths inhibited regeneration, involving photoreceptor CRY1. Downstream transcription factor HY5 mediated explant photoprotection, perhaps by promoting anthocyanin accumulation, a pigment also induced by cytokinin. Surprisingly, early light inhibition of shoot regeneration was dependent on polar auxin transport. Early exposure to ethylene stimulated dark-treated explants to regenerate, but inhibited light-treated explants. We propose that variability in long-term shoot regeneration may arise within the initial hours post-excision, from inadvertent, variable exposure of explants to light, modulated by hormones.


Subject(s)
Arabidopsis/physiology , Cotyledon/physiology , Light , Pigments, Biological/metabolism , Regeneration , Arabidopsis/radiation effects , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Basic-Leucine Zipper Transcription Factors/genetics , Basic-Leucine Zipper Transcription Factors/metabolism , Cotyledon/radiation effects , Cytokinins/metabolism , Ethylenes/metabolism , Indoleacetic Acids/metabolism , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Photoperiod , Plant Growth Regulators/metabolism , Reactive Oxygen Species/metabolism
7.
Plant J ; 73(5): 798-813, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23181633

ABSTRACT

Adventitious shoot organogenesis contributes to the fitness of diverse plant species, and control of this process is a vital step in plant transformation and in vitro propagation. New shoot meristems (SMs) can be induced by the conversion of lateral root primorida/meristems (LRP/LRMs) or callus expressing markers for this identity. To study this important and fascinating process we developed a high-throughput methodology for the synchronous initiation of LRP by auxin, and subsequent cytokinin-induced conversion of these LRP to SMs. Cytokinin treatment induces the expression of the shoot meristematic gene WUSCHEL (WUS) in converting LRP (cLRP) within 24-30 h, and WUS is required for LRP â†’ SM conversion. Subsequently, a transcriptional reporter for CLAVATA3 (CLV3) appeared 32-48 h after transfer to cytokinin, marking presumptive shoot stem cells at the apex of cLRP. Thus the spatial expression of these two components (WUS and CLV3) of a regulatory network maintaining SM stem cells already resembles that seen in a vegetative shoot apical meristem (SAM), suggesting the very rapid initiation and establishment of the new SMs. Our high-throughput methodology enabled us to successfully apply a systems approach to the study of plant regeneration. Herein we characterize transcriptional reporter expression and global gene expression changes during LRP â†’ SM conversion, elaborate the role of WUS and WUS-responsive genes in the conversion process, identify and test putative functional targets, perform a comparative analysis of domain-specific expression in cLRP and SM tissue, and develop a bioinformatic tool for examining gene expression in diverse regeneration systems.


Subject(s)
Arabidopsis Proteins/genetics , Arabidopsis/physiology , Gene Expression Regulation, Developmental , Homeodomain Proteins/genetics , Plant Growth Regulators/metabolism , Stem Cell Niche/physiology , Arabidopsis/cytology , Arabidopsis/genetics , Arabidopsis Proteins/metabolism , Cell Differentiation , Cytokinins/metabolism , Down-Regulation , Gene Expression Profiling , Gene Expression Regulation, Plant , Gene Knockout Techniques , Genes, Reporter , Genotype , Homeodomain Proteins/metabolism , Indoleacetic Acids/metabolism , Meristem/cytology , Meristem/genetics , Meristem/physiology , Oligonucleotide Array Sequence Analysis , Plant Roots/cytology , Plant Roots/genetics , Plant Roots/physiology , Plant Shoots/cytology , Plant Shoots/genetics , Plant Shoots/physiology , Plants, Genetically Modified , Recombinant Fusion Proteins , Regeneration , Tissue Culture Techniques , Transcriptome , Up-Regulation
8.
J Dance Med Sci ; 13(4): 101-7, 2009.
Article in English | MEDLINE | ID: mdl-19930811

ABSTRACT

The aim of this study was to develop a measurement tool, the "Performance Competence Evaluation Measure" (PCEM), for the evaluation of qualitative aspects of dance performance. The project had two phases. In the first phase a literature review was conducted to examine 1. the previous development of similar measurement tools, 2. descriptions of dance technique and dance performance applicable to the development of a qualitative measurement tool, and 3. theoretical models from somatic practices that evaluate and assess qualitative aspects of movement and dance activity. The second phase involved the development of a system for using PCEM, and testing its validity and reliability. Three judges from the professional dance community volunteered to test PCEM with a sample of 20 subjects from low-intermediate to advanced classes at a university dance program. The subjects learned a dance combination and were videotaped performing it on two separate occasions, eight weeks apart. The judges reviewed the videos in random order. Logical validity of PCEM was established through assessment by two faculty members of the university dance department and the three judges. Intra-rater and inter-rater reliability demonstrated correlation coefficients of 0.95 and 0.94, respectively. It was concluded that PCEM can serve as a useful measurement tool for future dance science research.


Subject(s)
Dancing , Professional Competence , Program Evaluation/methods , Students , Video Recording , Athletic Performance , Exercise Test/methods , Humans , Reproducibility of Results , Sampling Studies , Universities
9.
J Dance Med Sci ; 13(4): 108-14, 2009.
Article in English | MEDLINE | ID: mdl-19930812

ABSTRACT

This study assessed the inter-judge agreement, intra-judge reliability, and the specificity and sensitivity of a qualitative test for analyzing dancers' training and performance capabilities. Forty-one subjects representing groups of non-dancers (N = 9), beginners (N = 9), intermediates (N = 10), advanced (N = 7), and professionals (N = 6) were videotaped while performing compulsory and improvised segments of movement. The videotapes were then analyzed by three trained judges, using the unique scoring system devised by the author, for the following components: skill, space, time, energy, phrasing, and presence. Inter-judge agreement correlations and the overall intra-judge reliability coefficient were very high (r = .95 to .96, p < .0001, and R = .98, p < .0001, respectively). Specificity was .86, and sensitivity .97. It is concluded that the test described in the study is valid for use in both research and educational settings where qualitative analysis of dance performance across levels of expertise is useful.


Subject(s)
Athletic Performance , Dancing , Exercise Test/methods , Motor Skills , Videotape Recording , Adult , Analysis of Variance , Case-Control Studies , Curriculum , Female , Humans , Reproducibility of Results
10.
Plant Cell Physiol ; 50(1): 141-50, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19068493

ABSTRACT

Cell type-specific fluorescent gene expression markers are a prerequisite for various strategies in functional genomics and developmental biology. To increase the resolution of vascular tissue analysis and to identify more genes expressed in the vasculature, we searched for expression in vascular tissues within a new collection of transactivated enhancer trap lines. Among 33 lines with vascular expression, we identified five lines with expression profiles marking procambial or procambium-associated cell states. In stem cross-sections we identified one line with phloem- and four with xylem-specific expression, as well as nine lines with expression in both phloem and xylem and two with cambial expression. For all lines, we also report the expression patterns in different organs and developmental stages. Special features of expression patterns include a line with auxin-dependent expression domains. We determined the flanking sequences of 21 enhancer trap insertions, 16 of which are found in, or in close proximity to, annotated genes and thus may reflect the expression patterns of natural promoters. Finally, we analyzed the loss-of-function phenotypes of 14 putatively affected genes. Remarkably, mutations in a gene encoding a putative F-box protein were associated with an auxin-hypersensitive hypocotyl elongation response. Our compendium provides a diverse selection of markers for different vascular cell states, which can be used for targeted gene expression, cell type-specific transcript profiling and gene function assignment in the plant vascular system.


Subject(s)
Arabidopsis/genetics , Genes, Plant , Phloem/metabolism , Xylem/metabolism , Arabidopsis/growth & development , Arabidopsis/metabolism , DNA, Bacterial/genetics , DNA, Plant/genetics , Gene Expression Profiling , Gene Expression Regulation, Developmental , Gene Expression Regulation, Plant , Genes, Reporter , Mutagenesis, Insertional , Phloem/genetics , Xylem/genetics
11.
Arabidopsis Book ; 7: e0126, 2009.
Article in English | MEDLINE | ID: mdl-22303250

ABSTRACT

During embryogenesis a single cell gives rise to a functional multicellular organism. In higher plants, as in many other multicellular systems, essential architectural features, such as body axes and major tissue layers are established early in embryogenesis and serve as a positional framework for subsequent pattern elaboration. In Arabidopsis, the apicalbasal axis and the radial pattern of tissues wrapped around it are already recognizable in young embryos of only about a hundred cells in size. This early axial pattern seems to provide a coordinate system for the embryonic initiation of shoot and root. Findings from genetic studies in Arabidopsis are revealing molecular mechanisms underlying the initial establishment of the axial core pattern and its subsequent elaboration into functional shoots and roots. The genetic programs operating in the early embryo organize functional cell patterns rapidly and reproducibly from minimal cell numbers. Understanding their molecular details could therefore greatly expand our ability to generate plant body patterns de novo, with important implications for plant breeding and biotechnology.

12.
Plant Cell Rep ; 27(4): 655-66, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18084766

ABSTRACT

We have investigated the role of ethylene in shoot regeneration from cotyledon explants of Arabidopsis thaliana. We examined the ethylene sensitivity of five ecotypes representing both poor and prolific shoot regenerators and identified Dijon-G, a poor regenerator, as an ecotype with dramatically enhanced ethylene sensitivity. However, inhibiting ethylene action with silver nitrate generally reduced shoot organogenesis in ecotypes capable of regeneration. In ecotype Col-0, we found that ethylene-insensitive mutants (etr1-1, ein2-1, ein4, ein7) exhibited reduced shoot regeneration rates, whereas constitutive ethylene response mutants (ctr1-1, ctr1-12) increased the proportion of explants producing shoots. Our experiments with ethylene over-production mutants (eto1, eto2 and eto3) indicate that the ethylene biosynthesis inhibitor gene, ETO1, can act as an inhibitor of shoot regeneration. Pharmacological elevation of ethylene levels was also found to significantly increase the proportion of explants regenerating shoots. We determined that the hookless1 (hls1-1) mutant, a suppressor of the ethylene response phenotypes of ctr1 and eto1 mutants, is capable of dramatically enhancing shoot organogenesis. The effects of ACC and loss of HLS1 function on shoot organogenesis were found to be largely additive.


Subject(s)
Arabidopsis Proteins/metabolism , Arabidopsis/physiology , Ethylenes/pharmacology , Plant Roots/physiology , Arabidopsis/drug effects , Arabidopsis/growth & development , Arabidopsis Proteins/genetics , Mutation , Plant Growth Regulators/pharmacology , Plant Roots/drug effects , Plant Roots/growth & development
13.
J Dance Med Sci ; 12(4): 121-35, 2008.
Article in English | MEDLINE | ID: mdl-19618569

ABSTRACT

Turnout measurement procedures, results, and reporting formats vary in dance medicine and science research, making comparisons difficult. It is agreed that turnout results from summative contributions of the hip, knee, lower-leg, and the foot-ankle complex. However, the most frequently reported measurement is hip external rotation, and even this is measured in incompatible ways. No normative data exist for component and summative measures or for different categories of dancers, making screening, clinical assessment, and research problematic. Thus, there is a need to standardize component measurements, develop an inclusive measurement procedure for total turnout, and establish normative data for each measurement and for different categories of dancers. This review evaluates the 24 published articles that have reported original data for turnout assessment in dancers. Results are summarized and displayed for each article. In conclusion, recommendations are made for: use of selected hip external range of motion and tibial version measurements as the most important components of turnout; a procedure for assessing total turnout; adoption of conventions for reporting data in compatible forms; and the development of normative data sets for different categories of dancers.


Subject(s)
Arthrometry, Articular/methods , Dancing/physiology , Hip Joint/physiology , Leg/physiology , Range of Motion, Articular/physiology , Biomechanical Phenomena , Female , Humans , Leg Bones/physiology , Male , Posture
14.
J Infect Dis ; 192(3): 360-6, 2005 Aug 01.
Article in English | MEDLINE | ID: mdl-15995948

ABSTRACT

BACKGROUND: M01ZH09 (Salmonella enterica serovar Typhi [Ty2 aroC(-) ssaV(-)] ZH9) is a live oral-dose typhoid vaccine candidate. M01ZH09 was rationally modified with 2 independently attenuating mutations, including a novel mutation in Salmonella pathogenicity island (SPI)-2. We demonstrate that M01ZH09, in a single oral dose, is well tolerated and prompts broad immune responses, regardless of whether prevaccination with a bicarbonate buffer is given. METHODS: Thirty-two healthy adult subjects were randomized and given 5x109 cfu of M01ZH09, with (presentation 1) or without (presentation 2) prevaccination with a bicarbonate buffer. Immunogenicity data included Salmonella Typhi lipopolysaccharide (LPS)-specific immunoglobulin (Ig) A antibody-secreting cells (enzyme-linked immunospot [ELISPOT] assay), IgG serologic responses to Salmonella Typhi LPS, lymphocyte proliferation, and interferon (IFN)- gamma production. RESULTS: The vaccine was well tolerated; adverse events after vaccination were mild. No fever or prolonged vaccine shedding occurred. Immunogenicity data demonstrated that 88% and 93% of subjects who received presentation 1 and presentation 2, respectively, had a positive response by ELISPOT assay; 81% of subjects in both groups underwent IgG seroconversion on day 14. Both groups had similar cellular immune responses to presentation 1 and presentation 2; lymphocyte proliferation to Salmonella Typhi flagellin occurred in 63% and 67% of subjects, respectively, and 69% and 73% of subjects, respectively, had an increase in IFN- gamma production. CONCLUSION: The oral typhoid vaccine M01ZH09 is well tolerated and highly immunogenic in a single oral dose, with and without prevaccination with a bicarbonate buffer. Field studies to demonstrate protective efficacy are planned.


Subject(s)
Lipopolysaccharides/immunology , Typhoid Fever/immunology , Typhoid-Paratyphoid Vaccines/immunology , Administration, Oral , Adolescent , Adult , Antibodies, Bacterial/blood , Antibody Formation , Enzyme-Linked Immunosorbent Assay , Female , Freeze Drying , Humans , Immunoglobulin G/blood , Male , Middle Aged , Salmonella enterica/immunology , Salmonella typhi/immunology , Typhoid-Paratyphoid Vaccines/administration & dosage , Typhoid-Paratyphoid Vaccines/adverse effects , Typhoid-Paratyphoid Vaccines/toxicity , Vaccines, Attenuated
15.
Infect Immun ; 73(1): 362-8, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15618173

ABSTRACT

Novel candidate live oral vaccines based on a Salmonella enterica serovar Typhi ZH9 (Ty2 DeltaaroC DeltassaV) derivative that directed the expression of either the B subunit of Escherichia coli heat-labile toxin or hepatitis B virus core antigen from the bacterial chromosome using the in vivo inducible ssaG promoter were constructed. The levels of attenuation of the two S. enterica serovar Typhi ZH9 derivatives were similar to that of the parent as assessed by measuring the replication of bacteria within human macrophage-like U937 cells. The expression of heterologous antigen in the respective S. enterica serovar Typhi ZH9 derivatives was up-regulated significantly within U937 cells compared to similar S. enterica serovar Typhi ZH9 derivative bacteria grown in modified Luria-Bertani broth supplemented with aromatic amino acids. Immunization of mice with these S. enterica serovar Typhi ZH9 derivatives stimulated potent antigen-specific serum immunoglobulin G responses to the heterologous antigens.


Subject(s)
Bacterial Toxins/genetics , Chromosomes, Bacterial , Enterotoxins/genetics , Escherichia coli Proteins/genetics , Genetic Vectors , Hepatitis B Core Antigens/genetics , Promoter Regions, Genetic , Salmonella typhi/genetics , Administration, Intranasal , Animals , Antibodies, Bacterial/blood , Female , Humans , Immunoglobulin G/blood , Mice , Mice, Inbred BALB C , Salmonella typhi/immunology , U937 Cells
16.
Vaccine ; 22(25-26): 3243-55, 2004 Sep 03.
Article in English | MEDLINE | ID: mdl-15308346

ABSTRACT

DNA derived from regions upstream of the Salmonella enterica serovar Typhimurium ssaG gene were used to drive expression of different reporter genes in putative Salmonella vaccine strains. Expression from ssaG was shown to be significantly upregulated once Salmonella had entered murine or human macrophages, and levels of expression were dependent on the length of the ssaG 5' sequence incorporated. S. Typhimurium derivatives harbouring the Escherichia coli heat labile toxin B subunit (LT-B) fused to various lengths of the ssaG promoter region were also constructed as single copy chromosomal integrations. Expression of LT-B by these Salmonella derivatives was detected at significant levels after intra-macrophage survival and mice immunised with these derivatives mounted marked anti-LT-B humoral antibody responses.


Subject(s)
Antigens, Bacterial/biosynthesis , Antigens, Bacterial/immunology , Genes, Bacterial/immunology , Salmonella Vaccines/immunology , Salmonella typhimurium/immunology , Animals , Antigens, Bacterial/genetics , Base Sequence , Cell Survival , Cells, Cultured , Chromosomes, Bacterial/genetics , Chromosomes, Bacterial/immunology , Culture Media , DNA Primers , Flow Cytometry , Genes, Bacterial/genetics , Genes, Reporter/genetics , Humans , Immunoglobulin G/biosynthesis , Lac Operon/genetics , Macrophages/immunology , Mice , Mice, Inbred BALB C , Microscopy, Confocal , Molecular Sequence Data , Plasmids/genetics , Plasmids/immunology , Promoter Regions, Genetic/genetics , Promoter Regions, Genetic/immunology , Reverse Transcriptase Polymerase Chain Reaction , Salmonella Vaccines/genetics , Salmonella typhimurium/genetics , Vaccines, DNA/biosynthesis , Vaccines, DNA/immunology
17.
Genes Dev ; 17(12): 1469-74, 2003 Jun 15.
Article in English | MEDLINE | ID: mdl-12815068

ABSTRACT

Shoot branching is inhibited by auxin transported down the stem from the shoot apex. Auxin does not accumulate in inhibited buds and so must act indirectly. We show that mutations in the MAX4 gene of Arabidopsis result in increased and auxin-resistant bud growth. Increased branching in max4 shoots is restored to wild type by grafting to wild-type rootstocks, suggesting that MAX4 is required to produce a mobile branch-inhibiting signal, acting downstream of auxin. A similar role has been proposed for the pea gene, RMS1. Accordingly, MAX4 and RMS1 were found to encode orthologous, auxin-inducible members of the polyene dioxygenase family.


Subject(s)
Arabidopsis Proteins/physiology , Arabidopsis/genetics , Gene Expression Regulation, Plant , Oxygenases/physiology , Plant Shoots/physiology , Arabidopsis/drug effects , Arabidopsis/growth & development , Arabidopsis Proteins/genetics , Cloning, Molecular , DNA Transposable Elements , Indoleacetic Acids/pharmacology , Mutation , Oxygenases/genetics , Pisum sativum/genetics , Phylogeny , Plant Roots/genetics , Plant Roots/growth & development , Plant Shoots/drug effects , Plant Shoots/genetics , Sequence Homology, Nucleic Acid
18.
Plant Cell ; 15(2): 495-507, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12566587

ABSTRACT

A role for auxin in the regulation of shoot branching was described originally in the Thimann and Skoog model, which proposes that apically derived auxin is transported basipetally directly into the axillary buds, where it inhibits their growth. Subsequent observations in several species have shown that auxin does not enter axillary buds directly. We have found similar results in Arabidopsis. Grafting studies indicated that auxin acts in the aerial tissue; hence, the principal site of auxin action is the shoot. To delineate the site of auxin action, the wild-type AXR1 coding sequence, which is required for normal auxin sensitivity, was expressed under the control of several tissue-specific promoters in the auxin-resistant, highly branched axr1-12 mutant background. AXR1 expression in the xylem and interfascicular schlerenchyma was found to restore the mutant branching to wild-type levels in both intact plants and isolated nodes, whereas expression in the phloem did not. Therefore, apically derived auxin can suppress branching by acting in the xylem and interfascicular schlerenchyma, or in a subset of these cells.


Subject(s)
Arabidopsis/growth & development , Indoleacetic Acids/pharmacology , Plant Shoots/growth & development , Arabidopsis/drug effects , Arabidopsis/genetics , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Biological Transport/drug effects , Biological Transport/physiology , Gene Expression Regulation, Developmental , Gene Expression Regulation, Plant , Genetic Complementation Test , Growth Substances/genetics , Growth Substances/metabolism , Indoleacetic Acids/physiology , Mutation , Phenotype , Plant Growth Regulators/pharmacology , Plant Growth Regulators/physiology , Plant Shoots/drug effects , Promoter Regions, Genetic/genetics
19.
Vaccine ; 21(5-6): 538-48, 2003 Jan 17.
Article in English | MEDLINE | ID: mdl-12531654

ABSTRACT

The S. typhimurium strain (TML deltaaroC deltassaV) WT05, harbouring defined deletions in genes involved in both the aromatic biosynthesis pathway (aroC) and the Salmonella Pathogenicity Island-2 (SPI-2) (ssaV) was shown to be significantly attenuated in C57 BL/6 interferon gamma knockout mice following oral inoculation. Similarly, the S. typhi strain (Ty2 deltaaroC deltassaV) ZH9 harbouring the aroC and ssaV mutations propagated less efficiently than wild type in human macrophages. These studies demonstrated the attractive safety profile of the aroC ssaV mutant combination. Strains S. typhimurium (TML deltaaroC deltassaV ) WT05 and S. typhi (Ty2 deltaaroC deltassaV) ZH9 were subsequently tested as vaccine vectors to deliver E. coli heat-labile toxin (LT-B) mucosally to mice. Mice inoculated orally with S. typhimurium (TML deltaaroC deltassaV) WT05 expressing LT-B (WT05/LT-B) elicited high titres of both LT-specific serum IgG and intestinal IgA, although no specific IgA was detected in the vagina. Similarly, intranasal inoculation of mice with S. typhi (Ty2 deltaaroC deltassaV) ZH9 expressing LT-B (ZH9/LT-B) elicited even higher titres of LT-specific serum antibody as well as LT-specific Ig in the vagina. We conclude that deltaaroC deltassaV strains of Salmonella are highly attenuated and are promising candidates both as human typhoid vaccines and as vaccine vectors for the delivery of heterologous antigens.


Subject(s)
Bacterial Proteins/immunology , Bacterial Vaccines/immunology , Escherichia coli Proteins , Genetic Vectors/immunology , Hydrocarbons, Aromatic/metabolism , Membrane Proteins/immunology , Salmonella typhi/genetics , Salmonella typhi/immunology , Salmonella typhimurium/genetics , Salmonella typhimurium/immunology , Animals , Bacterial Toxins/biosynthesis , Bacterial Toxins/immunology , Cell Survival , Enterotoxins/biosynthesis , Enterotoxins/immunology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunity, Mucosal/immunology , Immunoglobulin G/biosynthesis , Immunoglobulin G/genetics , Interferon-gamma/genetics , Interferon-gamma/physiology , Intestines/immunology , Macrophages/immunology , Mice , Mice, Inbred BALB C , Mice, Knockout , Phenotype , Vagina/immunology
20.
Infect Immun ; 70(7): 3457-67, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12065485

ABSTRACT

The attenuation and immunogenicity of two novel Salmonella vaccine strains, Salmonella enterica serovar Typhi (Ty2 Delta aroC Delta ssaV, designated ZH9) and S. enterica serovar Typhimurium (TML Delta aroC Delta ssaV, designated WT05), were evaluated after their oral administration to volunteers as single escalating doses of 10(7), 10(8), or 10(9) CFU. ZH9 was well tolerated, not detected in blood, nor persistently excreted in stool. Six of nine volunteers elicited anti-serovar Typhi lipopolysaccharide (LPS) immunoglobulin A (IgA) antibody-secreting cell (ASC) responses, with three of three vaccinees receiving 10(8) and two of three receiving 10(9) CFU which elicited high-titer LPS-specific serum IgG. WT05 was also well tolerated with no diarrhea, although the administration of 10(8) and 10(9) CFU resulted in shedding in stools for up to 23 days. Only volunteers immunized with 10(9) CFU of WT05 mounted detectable serovar Typhimurium LPS-specific ASC responses and serum antibody responses were variable. These data indicate that mutations in type III secretion systems may provide a route to the development of live vaccines in humans and highlight significant differences in the potential use of serovars Typhimurium and Typhi.


Subject(s)
Bacterial Proteins/immunology , Membrane Proteins/immunology , Phosphorus-Oxygen Lyases/immunology , Salmonella Infections/prevention & control , Salmonella typhi/immunology , Salmonella typhimurium/immunology , Bacterial Proteins/genetics , Health Status , Healthy Volunteers , Humans , Membrane Proteins/genetics , Mutagenesis , Phosphorus-Oxygen Lyases/genetics , Salmonella typhi/genetics , Salmonella typhimurium/genetics , Typhoid Fever/immunology , Typhoid Fever/prevention & control , Vaccination
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