48 research outputs found
The sequence of rice chromosomes 11 and 12, rich in disease resistance genes and recent gene duplications
Background: Rice is an important staple food and, with the smallest cereal genome, serves as a reference species for studies on the evolution of cereals and other grasses. Therefore, decoding its entire genome will be a prerequisite for applied and basic research on this species and all other cereals. Results: We have determined and analyzed the complete sequences of two of its chromosomes, 11 and 12, which total 55.9 Mb (14.3% of the entire genome length), based on a set of overlapping clones. A total of 5,993 non-transposable element related genes are present on these chromosomes. Among them are 289 disease resistance-like and 28 defense-response genes, a higher proportion of these categories than on any other rice chromosome. A three-Mb segment on both chromosomes resulted from a duplication 7.7 million years ago (mya), the most recent large-scale duplication in the rice genome. Paralogous gene copies within this segmental duplication can be aligned with genomic assemblies from sorghum and maize. Although these gene copies are preserved on both chromosomes, their expression patterns have diverged. When the gene order of rice chromosomes 11 and 12 was compared to wheat gene loci, significant synteny between these orthologous regions was detected, illustrating the presence of conserved genes alternating with recently evolved genes. Conclusion: Because the resistance and defense response genes, enriched on these chromosomes relative to the whole genome, also occur in clusters, they provide a preferred target for breeding durable disease resistance in rice and the isolation of their allelic variants. The recent duplication of a large chromosomal segment coupled with the high density of disease resistance gene clusters makes this the most recently evolved part of the rice genome. Based on syntenic alignments of these chromosomes, rice chromosome 11 and 12 do not appear to have resulted from a single whole-genome duplication event as previously suggested
Seasonal and Pandemic Influenza Surveillance and Disease Severity
This chapter addresses the disease burden on the US population caused by the annual influenza epidemics or pandemic and the methods of influenza surveillance used to monitor and prevent the spread of the disease. The meaningful use of electronic health records for influenza research and surveillance are discussed with a focus on variations of influenza disease severity between seasons and between individual patients. Surveillance of severe disease cases can contribute to a more effective public health preparedness and response
Seasonal and Pandemic Influenza Surveillance and Disease Severity
This chapter addresses the disease burden on the US population caused by the annual influenza epidemics or pandemic and the methods of influenza surveillance used to monitor and prevent the spread of the disease. The meaningful use of electronic health records for influenza research and surveillance are discussed with a focus on variations of influenza disease severity between seasons and between individual patients. Surveillance of severe disease cases can contribute to a more effective public health preparedness and response
SAFETY AND IMMUNOGENICITY OF A NATIONAL COMBINED VACCINE AGAINST PERTUSSIS, DIPHTHERIA, TETANUS, HEPATITIS B AND Hib-INFECTION, CONTAINING ACELLULAR PERTUSSIS COMPONENT, DURING IMMUNIZATION OF ADULTS
Aim. Study safety, reactogenicity and immunologic effectiveness of a national combined vaccine against diphtheria, pertussis (acellular component), tetanus, hepatitis B and Hib-infection during immunization of volunteers aged 18 - 60 years. Materials and methods. The study was carried out in accordance with ethical standards and requirements, regulated by Helsinki declaration and Good clinical practice (ICHGCP). In a simple non-randomized clinical trial 20 adult volunteers took part, the mean age of those was 46.9 years. Results. Registered post-vaccination reactions (both local and systemic) were mild and of moderate degree of severity, stopped independently after 2 - 3 days without administration of drug treatment. Postvaccinal complications were not noted. Parameters of general and biochemical analysis of blood, urine, IgE content in dynamics of immunization were within normal limits. A single administration of aAPDT-HepB+Hib to individuals aged 18 - 60 years resulted in development of antibodies against all the components of the preparation. Seroconversion factor fluctuated from 6.9 to 53.5. Conclusion. The results obtained allow to recommend the vaccine for evaluation of its safety, reactogenicity, immunologic and prophylaxis effectiveness in randomized clinical observation trials in children
RESULTS OF A MULTICENTER CLINICAL STUDY OF A NEW COMBINATION VACCINE DTaP-HepB+Hib PRODUCTION OF THE CPA «MICROGEN» FOR IMMUNIZATION OF CHILDREN 6 MONTHS
Aim. The aim of the study is evaluate of reactogenicity, safety and immunogenicity of the native combined vaccine DTaP-HepB+Hib. Materials and methods. Assessment of reactogenicity, safety and immunogenicity of the drug is investigated in a multicenter, comparative, randomized, simple-blind clinical trial of immunization of children 6 months (the comparator vaccine DTaP-HepB combined vaccine, Hiberix®). Results. The native combined vaccine DTaP-HepB+Hib is characterized by good tolerability, high safety profile and a pronounced immunogenicity. In terms of seroprotection, seroconversion and geometric mean titers of antibodies comparable to that used in Russia of vaccines DTP-HBV and Hiberix®. Conclusion. Vaccine DTaP-HepB+Hib can be recommended for registration in the territory of the Russian Federation for the prevention of pertussis, diphtheria, tetanus, hepatitis B and Hib-infection
Complete Genome Sequence of the Broad-Host-Range Vibriophage KVP40: Comparative Genomics of a T4-Related Bacteriophage
The complete genome sequence of the T4-like, broad-host-range vibriophage KVP40 has been determined. The genome sequence is 244,835 bp, with an overall G+C content of 42.6%. It encodes 386 putative protein-encoding open reading frames (CDSs), 30 tRNAs, 33 T4-like late promoters, and 57 potential rho-independent terminators. Overall, 92.1% of the KVP40 genome is coding, with an average CDS size of 587 bp. While 65% of the CDSs were unique to KVP40 and had no known function, the genome sequence and organization show specific regions of extensive conservation with phage T4. At least 99 KVP40 CDSs have homologs in the T4 genome (Blast alignments of 45 to 68% amino acid similarity). The shared CDSs represent 36% of all T4 CDSs but only 26% of those from KVP40. There is extensive representation of the DNA replication, recombination, and repair enzymes as well as the viral capsid and tail structural genes. KVP40 lacks several T4 enzymes involved in host DNA degradation, appears not to synthesize the modified cytosine (hydroxymethyl glucose) present in T-even phages, and lacks group I introns. KVP40 likely utilizes the T4-type sigma-55 late transcription apparatus, but features of early- or middle-mode transcription were not identified. There are 26 CDSs that have no viral homolog, and many did not necessarily originate from Vibrio spp., suggesting an even broader host range for KVP40. From these latter CDSs, an NAD salvage pathway was inferred that appears to be unique among bacteriophages. Features of the KVP40 genome that distinguish it from T4 are presented, as well as those, such as the replication and virion gene clusters, that are substantially conserved
The complete genome sequence of the \u3ci\u3eArabidopsis\u3c/i\u3e and tomato pathogen \u3ci\u3ePseudomonas syringae\u3c/i\u3e pv. \u3ci\u3etomato\u3c/i\u3e DC3000
We report the complete genome sequence of the model bacterial pathogen Pseudomonas syringae pathovar tomato DC3000 (DC3000), which is pathogenic on tomato and Arabidopsis thaliana. The DC3000 genome (6.5 megabases) contains a circular chromosome and two plasmids, which collectively encode 5,763 ORFs. We identified 298 established and putative virulence genes, including several clusters of genes encoding 31 confirmed and 19 predicted type III secretion system effector proteins. Many of the virulence genes were members of paralogous families and also were proximal to mobile elements, which collectively comprise7%of the DC3000 genome. The bacterium possesses a large repertoire of transporters for the acquisition of nutrients, particularly sugars, as well as genes implicated in attachment to plant surfaces. Over 12% of the genes are dedicated to regulation, which may reflect the need for rapid adaptation to the diverse environments encountered during epiphytic growth and pathogenesis. Comparative analyses confirmed a high degree of similarity with two sequenced pseudomonads, Pseudomonas putida and Pseudomonas aeruginosa, yet revealed 1,159 genes unique to DC3000, of which 811 lack a known function. Includes published article and additional supporting materials
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Whole-genome sequence analysis of pseudomonas syringae pv. phaseolicola 1448A reveals divergence among pathovars in genes involved in virulence and transposition
Pseudomonas syringae pv. phaseolicola, a gram-negative bacterial plant pathogen, is the causal agent of halo blight of bean. In this study, we report on the genome sequence of P. syringae pv. phaseolicola isolate 1448A, which encodes 5,353 open reading frames (ORFs) on one circular chromosome (5,928,787 bp) and two plasmids (131,950 bp and 51,711 bp). Comparative analyses with a phylogenetically divergent pathovar, P. syringae pv. tomato DC3000, revealed a strong degree of conservation at the gene and genome levels. In total, 4,133 ORFs were identified as putative orthologs in these two pathovars using a reciprocal best-hit method, with 3,941 ORFs present in conserved, syntenic blocks. Although these two pathovars are highly similar at the physiological level, they have distinct host ranges; 1448A causes disease in beans, and DC3000 is pathogenic on tomato and Arabidopsis. Examination of the complement of ORFs encoding virulence, fitness, and survival factors revealed a substantial, but not complete, overlap between these two pathovars. Another distinguishing feature between the two pathovars is their distinctive sets of transposable elements. With access to a fifth complete pseudomonad genome sequence, we were able to identify 3,567 ORFs that likely comprise the core Pseudomonas genome and 365 ORFs that are P. syringae specific