Antibiotic resistant pathogens

The selection of transformed cells is achieved using a conferred selectable trait, most commonly antibiotic resistance. Only transformed cells with the conferred resistance trait are able to survive and reproduce. However, the use of antibiotics as a media component for commercial protein production is problematic for at least two reasons. First, residual antibiotic would be a highly undesirable contaminant in the final product. Second, the recurrent use of antibiotics increases the likelihood that antibiotic-resistant pathogen strains will develop. Recent studies indicate that antibiotic selection is not necessary during every passage (or generation). 

The ability of a light-drug combination to kill microorganisms is not a new idea and has been known for over 100 years [3]. In fact the concept of PDT was initiated in 1900 when Raab described the antimicrobial action of acridine and light on Paramecium species [4], Flowever, only recently has the search for alternative treatments for antibiotic-resistant pathogens stimulated the PACT development. 

Swayze (4) prepared 2-deoxystreptamine aromatic derivatives, (IV), which showed broad-spectrum activity against antibiotic-resistant pathogens. 

Tomasz A. Multiple-antibiotic-resistant pathogenic bacteria. A report on the Rockefeller University Workshop. N Engl J Med 1994 330(17) 1247-51. 

Clearly two distinct issues arise from these observations. The first is whether the development of nonsusceptibility to antiseptics by nosocomial pathogens, skin flora, and other microorganisms results in decreased clinical efficacy of the topical antiseptics used in healthcare settings. The second issue is whether the emergence of resistance to the antiseptics will result in cross-resistance to clinically useful antibiotics. The concern in the latter case is that the wide availability and use of antiseptics and the selection pressure they provide will counterselect for antibiotic resistant pathogens. 

In the current climate of ever-increasing strains of antibiotic-resistant pathogens, careful consideration of antibiotic selection is necessary. 

Moreover, 47 shows selective response to the lysates of bacteria (e.g., Escherichia coli) containing different types of P-lactamases. This result provides a simple, low-cost strategy to identify P-lactam antibiotic resistant pathogens and to screen the inhibitors of P-lactamases [86]. 

In particular, the authors wanted to associate the capsids with Staphylococcus aureus bacteria, allowing them to kill antibiotic-resistant pathogens specifically through the use of... 

Invisible killers such as Methicillin Resistant Staphylococcus aureus (MRSA) and other antibiotic resistant pathogens such as Clostridium difficile are a major cause of morbidity and mortality within hospitals worldwide. Current statistics put Ae instances of Hospital Acquired Infection at 300,000 per year incurring an added cost to the health service due to H.A.I. s. In 2000 the estimated cost to the NHS was as much as 1 billion. With instances of HAI s increasing (cases of C-DifBcile rose by 17% in 2005) the need to prevent cross-infection and reduce environmental contamination in hospitals has never been greater. 

D. J. Weber, P. D. Raasch and W. A. Rutala, Nosocomial infections in the ICU The growing importance of antibiotic-resistant pathogens. 

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