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1.
Rachaneeporn Tiyawisutsri Matthew TG Holden Sarinna Tumapa Sirirat Rengpipat Simon R Clarke Simon J Foster William C Nierman Nicholas PJ Day Sharon J Peacock 《BMC microbiology》2007,7(1):19
Background
The bacterial biothreat agents Burkholderia mallei and Burkholderia pseudomallei are the cause of glanders and melioidosis, respectively. Genomic and epidemiological studies have shown that B. mallei is a recently emerged, host restricted clone of B. pseudomallei. 相似文献2.
Stefan TG Bruijnen Mignon AC van der Weijden Joannes P Klein Otto S Hoekstra Ronald Boellaard J Christiaan van Denderen Ben AC Dijkmans Alexandre E Voskuyl Irene E van der Horst-Bruinsma Conny J van der Laken 《Arthritis research & therapy》2012,14(2):R71
Introduction
Positron Emission Tomography - Computer Tomography (PET-CT) is an interesting imaging technique to visualize Ankylosing Spondylitis (AS) activity using specific PET tracers. Previous studies have shown that the PET tracers [18F]FDG and [11C](R)PK11195 can target inflammation (synovitis) in rheumatoid arthritis (RA) and may therefore be useful in AS. Another interesting tracer for AS is [18F]Fluoride, which targets bone formation. In a pilot setting, the potential of PET-CT in imaging AS activity was tested using different tracers, with Magnetic Resonance Imaging (MRI) and conventional radiographs as reference.Methods
In a stepwise approach different PET tracers were investigated. First, whole body [18F]FDG and [11C](R)PK11195 PET-CT scans were obtained of ten AS patients fulfilling the modified New York criteria. According to the BASDAI five of these patients had low and five had high disease activity. Secondly, an extra PET-CT scan using [18F]Fluoride was made of two additional AS patients with high disease activity. MRI scans of the total spine and sacroiliac joints were performed, and conventional radiographs of the total spine and sacroiliac joints were available for all patients. Scans and radiographs were visually scored by two observers blinded for clinical data.Results
No increased [18F]FDG and [11C](R)PK11195 uptake was noticed on PET-CT scans of the first 10 patients. In contrast, MRI demonstrated a total of five bone edema lesions in three out of 10 patients. In the two additional AS patients scanned with [18F]Fluoride PET-CT, [18F]Fluoride depicted 17 regions with increased uptake in both vertebral column and sacroiliac joints. In contrast, [18F]FDG depicted only three lesions, with an uptake of five times lower compared to [18F]Fluoride, and again no [11C](R)PK11195 positive lesions were found. In these two patients, MRI detected nine lesions and six out of nine matched with the anatomical position of [18F]Fluoride uptake. Conventional radiographs showed structural bony changes in 11 out of 17 [18F]Fluoride PET positive lesions.Conclusions
Our PET-CT data suggest that AS activity is reflected by bone activity (formation) rather than inflammation. The results also show the potential value of PET-CT for imaging AS activity using the bone tracer [18F]Fluoride. In contrast to active RA, inflammation tracers [18F]FDG and [11C](R)PK11195 appeared to be less useful for AS imaging. 相似文献3.
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N. N. Lopatina T. G. Zachepilo I. V. Ryzhova V. B. Smirnov E. G. Chesnokova 《Journal of Evolutionary Biochemistry and Physiology》2004,40(3):271-276
Participation of non-NMDA-receptors in associative learning in the honeybee was analyzed using a complex approach. There were studied effects of systemic and intracerebral AMPA injections on retention of the elaborated conditional reflex in short-term memory, on dynamics of the bioelectrical activity of neurons of calyx of the mushroom bodies, and on the limb locomotor activity. It has been shown that the systemic and intracerebral AMPA injections stimulate processes of short-term memory and activate bioelectrical activity of neurons of the mushroom body medial calyx. Antagonist of AMPA-receptors NS-257 HCl suppressed spontaneous activity of these neurons. The observed processes did not depend on the character of locomotor activity. These results confirm the hypothesis proposed earlier about involvement of non-NMDA-receptors in the process of associative learning. 相似文献
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Li-Yang Hsu Simon R Harris Monika A Chlebowicz Jodi A Lindsay Tse-Hsien Koh Prabha Krishnan Thean-Yen Tan Pei-Yun Hon Warren B Grubb Stephen D Bentley Julian Parkhill Sharon J Peacock Matthew TG Holden 《Genome biology》2015,16(1)
BackgroundIn the past decade, several countries have seen gradual replacement of endemic multi-resistant healthcare-associated methicillin-resistant Staphylococcus aureus (MRSA) with clones that are more susceptible to antibiotic treatment. One example is Singapore, where MRSA ST239, the dominant clone since molecular profiling of MRSA began in the mid-1980s, has been replaced by ST22 isolates belonging to EMRSA-15, a recently emerged pandemic lineage originating from Europe.ResultsWe investigated the population structure of MRSA in Singaporean hospitals spanning three decades, using whole genome sequencing. Applying Bayesian phylogenetic methods we report that prior to the introduction of ST22, the ST239 MRSA population in Singapore originated from multiple introductions from the surrounding region; it was frequently transferred within the healthcare system resulting in a heterogeneous hospital population. Following the introduction of ST22 around the beginning of the millennium, this clone spread rapidly through Singaporean hospitals, supplanting the endemic ST239 population. Coalescent analysis revealed that although the genetic diversity of ST239 initially decreased as ST22 became more dominant, from 2007 onwards the genetic diversity of ST239 began to increase once more, which was not associated with the emergence of a sub-clone of ST239. Comparative genomic analysis of the accessory genome of the extant ST239 population identified that the Arginine Catabolic Mobile Element arose multiple times, thereby introducing genes associated with enhanced skin colonization into this population.ConclusionsOur results clearly demonstrate that, alongside clinical practice and antibiotic usage, competition between clones also has an important role in driving the evolution of nosocomial pathogen populations.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-015-0643-z) contains supplementary material, which is available to authorized users. 相似文献6.
Eike J Steinig Patiyan Andersson Simon R Harris Derek S Sarovich Anand Manoharan Paul Coupland Matthew TG Holden Julian Parkhill Stephen D Bentley D Ashley Robinson Steven YC Tong 《BMC genomics》2015,16(1)
Background
Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of hospital-associated infection, but there is growing awareness of the emergence of multidrug-resistant lineages in community settings around the world. One such lineage is ST772-MRSA-V, which has disseminated globally and is increasingly prevalent in India. Here, we present the complete genome sequence of DAR4145, a strain of the ST772-MRSA-V lineage from India, and investigate its genomic characteristics in regards to antibiotic resistance and virulence factors.Results
Sequencing using single-molecule real-time technology resulted in the assembly of a single continuous chromosomal sequence, which was error-corrected, annotated and compared to nine draft genome assemblies of ST772-MRSA-V from Australia, Malaysia and India. We discovered numerous and redundant resistance genes associated with mobile genetic elements (MGEs) and known core genome mutations that explain the highly antibiotic resistant phenotype of DAR4145. Staphylococcal toxins and superantigens, including the leukotoxin Panton-Valentinin Leukocidin, were predominantly associated with genomic islands and the phage φ-IND772PVL. Some of these mobile resistance and virulence factors were variably present in other strains of the ST772-MRSA-V lineage.Conclusions
The genomic characteristics presented here emphasize the contribution of MGEs to the emergence of multidrug-resistant and highly virulent strains of community-associated MRSA. Antibiotic resistance was further augmented by chromosomal mutations and redundancy of resistance genes. The complete genome of DAR4145 provides a valuable resource for future investigations into the global dissemination and phylogeography of ST772-MRSA-V.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1599-9) contains supplementary material, which is available to authorized users. 相似文献7.
Victoria Küttner Claudia Mack Kristoffer TG Rigbolt Johannes S Kern Oliver Schilling Hauke Busch Leena Bruckner‐Tuderman Jörn Dengjel 《Molecular systems biology》2013,9(1)
The mammalian cellular microenvironment is shaped by soluble factors and structural components, the extracellular matrix, providing physical support, regulating adhesion and signalling. A global, quantitative mass spectrometry strategy, combined with bioinformatics data processing, was developed to assess proteome differences in the microenvironment of primary human fibroblasts. We studied secreted proteins of fibroblasts from normal and pathologically altered skin and their post‐translational modifications. The influence of collagen VII, an important structural component, which is lost in genetic skin fragility, was used as model. Loss of collagen VII had a global impact on the cellular microenvironment and was associated with proteome alterations highly relevant for disease pathogenesis including decrease in basement membrane components, increase in dermal matrix proteins, TGF‐β and metalloproteases, but not higher protease activity. The definition of the proteome of fibroblast microenvironment and its plasticity in health and disease identified novel disease mechanisms and potential targets of intervention. 相似文献
8.
N. G. Lopatina T. H. Zachepilo N. G. Kamyshev N. I. Chalisova 《Journal of Evolutionary Biochemistry and Physiology》2017,53(2):123-128
This study addresses the influence of combinations of two encoded amino acids with opposite, memory-inhibiting and memory-enhancing, effects on short-term and long-term memory formation in the honeybee. Experimentation was based on the classical proboscis extension response conditioning by a single-trial exposure to clove odor with a sucrose solution reward. The presence of the acquired conditioned response was tested 1 min (short-term memory) and 180 min (long-term memory) after the learning trial. The data obtained suggest a stimulatory (memory-enhancing) effect of the combination of two amino acids, individual effects of which are opposite. The stimulatory amino acid was present in the mixture in all the trials (8 combinations) at a subthreshold concentration, i.e. it did not influence memory formation. In some trials, the stimulatory effect of an amino acid mixture (for example, stimulatory aspartic acid combined with inhibitory lysine or serine) significantly exceeded that of a single stimulatory amino acid applied at a threshold concentration. Interestingly, the effect of amino acid combinations on memory formation in honeybees resembles their effect on cell proliferation in rat tissue explants of various origin. 相似文献
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