Academic literature on the topic 'Community-associated MRSA'

Staphylococcal species are common commensals of the skin and mucous membranes of humans and animals but only in very recent years has zoonotic infections been recognised. They can also be associated with infection and disease, especially coagulase positive organisms. Staphylococcus aureus is relatively frequently carried by humans in the nasal passages and is a cause of infections in people including bacteraemias in hospitalised patients. More recently some strains of Staphylococcus aureus have acquired a resistance gene (mecA) which renders them resistant to meticillin (meticillin-resistant Staphylococcus aureus, MRSA). MRSA isolates are of major importance in healthcare situations as well as increasingly in the community. Animals can also be carriers of Staphylococcus aureus although less frequently than humans and MRSA can be carried or infect several different host species. For companion animals such as dogs and cats, the most frequently isolated MRSA strains are similar to the common local human healthcare strains; thus for the UK, EMRSA-15 and -16. This suggests a reverse zoonosis with spill over from the human population into their companion animals. In horses the situation is different, with some horses carrying or infected with human epidemic strains but others infected with strains less frequently seen in people. For food-producing animals the picture is different again with a particular strain, ST398, which appears to circulate endemically in animal populations, such as pigs, and can spill over into the human population where it can cause carriage as well as infection and disease. The transmission appears to be by direct contact with animals rather than through the food-chain.Where risk factors for infection with MRSA have been studied in animals they appear similar to some of the risks for human infection. Therefore, for control of MRSA in animals measures such as improved hygiene and good antibacterial stewardship are important.

Staphylococcus aureus is among the most common opportunistic infections worldwide, as it is found as part of the flora in many parts of the body. S. aureus is the leading cause of nosocomial infections with its ability to rapidly colonize the infected area, high virulence, rapid adaptation to environmental conditions, and the ability to develop very fast and effective resistance even to new generation antibiotics. Methicillin-resistant Staphylococcus aureus (MRSA), first identified in the 1960s, is one of the most successful modern pathogens, becoming an important factor in hospitals in the 1980s. MRSA is an important factor, especially in hospitalized patients and healthcare-associated infections. Patients colonized with S. aureus and MRSA are at risk for community-acquired infections. It is critical that multidrug resistance reduces treatment options in MRSA infections and MRSA strains. These microorganisms have been the subject of research for years as they spread and become resistant in both social and medical settings and cause great morbidity and mortality. With the rapid spread of resistance among bacteria, antibiotic resistance has increased the cost of health care, and this has become the factor limiting the production of new antibiotics.

This chapter explores infections of the deep spaces of the neck, which are becoming more common. Patients with deep neck infections are frequently either diabetic, HIV-infected (irrespective of antiretroviral therapy status), or immunocompromised in some other way. In addition, a history of injection drug use (IDU), neutropenia, or exogenous steroid therapy is common. A dental source is frequently present. Deep neck infections are usually polymicrobial, reflecting the oral cavity source of most of these infections. When associated with IDU, community-acquired methicillin-resistant Staphylococcus aureus (MRSA) is the most likely organism encountered. Attempts to devise an algorithm-based approach to help with clinical decision-making have been made. Factors considered important include the presence/absence of airway obstruction, depth of neck involvement, ability to open mouth, ability to swallow, and any recent antibiotic usage.

Both humans and domestic animals can get the sickness brought on by the bacterium. In certain animal species, it could lead to severe mastitis. Staphylococcus aureus is the cause of mastitis in cattle in around 30% of clinical and subclinical cases. The elderly, babies, and those with impaired immune systems are more susceptible to S. aureus infection than healthy individuals. S. aureus is the main source of nosocomial and community-associated infections, and it has become an issue due to the organism's rising incidence of antibiotic resistance. Numerous virulence variables were associated to its pathogenecity. Chronic inflammatory skin disease known as atopic dermatitis (AD) can be directly attributed to the presence of persistent bacterial infections such S. aureus. These diseases primarily affect newborns and children. According to data, the range might be between 18 and 22% in wealthy nations. Methicillin-Resistant Numerous illnesses, including infections of the skin and soft tissues, endocarditis, infections of the bones and joints, and others, are brought on by Staphylococcus aureus. The most prevalent and potentially fatal of these infections is MRSA bacteremia, which has a high death rate and several comorbidities. In this article we have focused on multidrug resistance of S. aureus and others pathogenic microorganisms.

The most important microbe in humans is Staphylococcus aureus, which has caused worldwide dispersion in both nosocomial and community settings. The impact of Gram-positive Staphylococcus Aureuson the host is extremely detrimental to illness development. The life form is noteworthy for its ability to receive anti-toxin protection from a variety of anti-toxin classes. The development and distribution of methicillin-resistant Staphylococcus Aureus (MRSA) strains, which are generally multi-drug resistant in clinics and, as a result, in the population, cause severe mortality and bleakness. The research of MRSA illness transmission has advanced since its underlying event, which necessitates a complete clinical approach to dealing with take on this microorganism. For long term use drug of choice is vancomycine nevertheless its efficacy has been put to the test by rise in opposition. More modern anti-MRSA anti-infection medicines have been approved for clinical usage in the last 10 years or so. The aim of this chapter is to offer related data on the genus Staphylococcus and the evolution of antibiotic resistance in addition a discussion of the most important antibiotic resistance mechanisms. Although they are notorious for causing anti-infection blockage, there is a constant need for exploring innovative MRSA antagonists from various sources, including plants, and assessing non-anti-toxin draws close.

Staphylococcus aureus causes a wide range of diseases, including both community-associated and hospital-acquired infections such as abscesses, wound infections, osteomyelitis, endocarditis and septicemia. Regulation of the expression of various virulence factors is initiated through complex coordination between two-component systems, transcriptional regulatory proteins and regulatory small RNAs (sRNAs). S.aureus uses many sRNA and RNA–RNA interactions mediated the regulation of the expression of genes post-transcriptionally, but it uses few sigma factors to initiate the transcription function. sRNA transcripts are encoded within intergenic regions or in antisense orientation to mRNA transcripts, and sRNA regulation plays a central role in the response to stress stimuli encountered by pathogens during infection. One of the most intriguing examples of sRNA-mediated post-transcriptional regulation is RNAIII from S.aureus, which interacts with and regulates various RNA targets involved in virulence. Several genes known to be regulated by RNAIII have been demonstrated to be regulated by the sarA locus, independent of its effect on the expression of RNAIII. We discuss the potential role of small RNA (sRNA) in the pathogenesis and virulence factors production of Staphylococcus aureus.

Fruit quality is determined by numerous genetic traits that affect taste, aroma, texture, pigmentation, nutritional value and duration of shelf-life. The molecular basis of many of these important traits is poorly understood and it’s understanding offers an excellent opportunity for adding value to agricultural products. Improvement of melon fruit quality was the primary goal of the project. The original objectives of the project were: The isolation of a minimum of 1000 fruit specific ESTs. The development of a microarray of melon fruit ESTs. The analysis of gene expression in melon using melon and tomato fruit enriched microarrays. A comprehensive study of fruit gene expression of the major cucurbit crops. In our current project we have focused on the development of genomics tools for the enhancement of melon research with an emphasis on fruit, specifically the first public melon EST collection. We have also developed a database to relay this information to the research community and developed a publicly available microarray. The release of this information was one of the catalysts for the establishment of the International Cucurbit Genomic Initiative (ICuGI, Barcelona, Spain, July 2005) aimed at collecting and generating up to 100,000 melon EST sequences in 2006, leveraging a significant expansion of melon genomic resources. A total of 1000 ESTs were promised under the original proposal (Objective 1). Non-subtracted mature fruit and young fruit flesh of a climacteric variety in addition to a non-climacteric variety resulted in the majority of additional EST sequences for a total of 4800 attempted reads. 3731 high quality sequences from independent ESTs were assembled, representing 2,467 melon unigenes (1,873 singletons, 594 contigs). In comparison, as of June 2004, a total of 170 melon mRNA sequences had been deposited in GENBANK. The current project has thus resulted in nearly five- fold the number of ESTs promised and ca. 15-fold increase in the depth of publicly available melon gene sequences. All of these sequences have been deposited in GENBANK and are also available and searchable via multiple approaches in the public database (http://melon.bti.cornell.edu). Our database was selected as the central location for presentation of public melon EST data of the International Cucurbit Genomic Initiative. With the available unigenes we recently constructed a microarray, which was successfully applied in hybridizations (planned public release by August 2006). Current gene expression analyses focus on fruit development and on comparative studies between climacteric and non-climacteric melons. Earlier, expression profiling was conducted using macroarrays developed at the preliminary stage of the project. This analysis replaced the study of tomato microarray following the recommendations of the reviewers and the panel of the original project. Comparative study between melon and other cucurbit crops have begun, mainly with watermelon, in collaboration with Dr. Amnon Levi (USDA-ARS). In conclusion, all four objectives have been addressed and achieved. In the continuation project that have been approved we plan to apply the genomic tools developed here to achieve detailed functional analyses of genes associated with major metabolic pathway.

Fruit quality is determined by numerous genetic factors that affect taste, aroma, ‎color, texture, nutritional value and shelf life. To unravel the genetic components ‎involved in the metabolic pathways behind these traits, the major goal of the project was to identify novel genes that are involved in, or that regulate, these pathways using correlation analysis between genotype, metabolite and gene expression data. The original and specific research objectives were: (1) Collection of replicated fruit from a population of 96 RI lines derived from parents distinguished by great diversity in fruit development and quality phenotypes, (2) Phenotypic and metabolic profiling of mature fruit from all 96 RI lines and their parents, (3) 454 pyrosequencing of cDNA representing mRNA of mature fruit from each line to facilitate gene expression analysis based on relative EST abundance, (4) Development of a database modeled after an existing database developed for tomato introgression lines (ILs) to facilitate online data analysis by members of this project and by researchers around the world. The main functions of the database will be to store and present metabolite and gene expression data so that correlations can be drawn between variation in target traits or metabolites across the RI population members and variation in gene expression to identify candidate genes which may impact phenotypic and chemical traits of interest, (5) Selection of RI lines for segregation and/or hybridization (crosses) analysis to ascertain whether or not genes associated with traits through gene expression/metabolite correlation analysis are indeed contributors to said traits. The overall research strategy was to utilize an available recombinant inbred population of melon (Cucumis melo L.) derived from phenotypically diverse parents and for which over 800 molecular markers have been mapped for the association of metabolic trait and gene expression QTLs. Transcriptomic data were obtained by high throughput sequencing using the Illumina platform instead of the originally planned 454 platform. The change was due to the fast advancement and proven advantages of the Illumina platform, as explained in the first annual scientific report. Metabolic data were collected using both targeted (sugars, organic acids, carotenoids) and non-targeted metabolomics analysis methodologies. Genes whose expression patterns were associated with variation of particular metabolites or fruit quality traits represent candidates for the molecular mechanisms that underlie them. Candidate genes that may encode enzymes catalyzingbiosynthetic steps in the production of volatile compounds of interest, downstream catabolic processes of aromatic amino acids and regulatory genes were selected and are in the process of functional analyses. Several of these are genes represent unanticipated effectors of compound accumulation that could not be identified using traditional approaches. According to the original plan, the Cucurbit Genomics Network (http://www.icugi.org/), developed through an earlier BARD project (IS-3333-02), was expanded to serve as a public portal for the extensive metabolomics and transcriptomic data resulting from the current project. Importantly, this database was also expanded to include genomic and metabolomic resources of all the cucurbit crops, including genomes of cucumber and watermelon, EST collections, genetic maps, metabolite data and additional information. In addition, the database provides tools enabling researchers to identify genes, the expression patterns of which correlate with traits of interest. The project has significantly expanded the existing EST resource for melon and provides new molecular tools for marker-assisted selection. This information will be opened to the public by the end of 2013, upon the first publication describing the transcriptomic and metabolomics resources developed through the project. In addition, well-characterized RI lines are available to enable targeted breeding for genes of interest. Segregation of the RI lines for specific metabolites of interest has been shown, demonstrating the utility in these lines and our new molecular and metabolic data as a basis for selection targeting specific flavor, quality, nutritional and/or defensive compounds. To summarize, all the specific goals of the project have been achieved and in many cases exceeded. Large scale trascriptomic and metabolomic resources have been developed for melon and will soon become available to the community. The usefulness of these has been validated. A number of novel genes involved in fruit ripening have been selected and are currently being functionally analyzed. We thus fully addressed our obligations to the project. In our view, however, the potential value of the project outcomes as ultimately manifested may be far greater than originally anticipated. The resources developed and expanded under this project, and the tools created for using them will enable us, and others, to continue to employ resulting data and discoveries in future studies with benefits both in basic and applied agricultural - scientific research.