antimicrobial resistance in pathogens not only in hospitals but also in the community has become an important public health problem. the aim of this study was to determine the antimicrobial resistance patterns of predominant pathogens from hospitalized and outpatients in a university hospital in tehran, iran. a total of 820 samples of common gram-negative and gram-positive bacteria were collect...

Current antibiotic testing does not include the potential influence of host cell environment on microbial susceptibility and antibiotic resistance, hindering appropriate therapeutic intervention. We devised a strategy to identify the presence of host-pathogen interactions that alter antibiotic efficacy in vivo. Our findings revealed a bacterial mechanism that promotes antibiotic resistance in v...

Background/introduction Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen that particularly threatens immunocompromised patients who are prone to develop infections that are less and less responsive to regular treatments. Moreover, MRSA can cause abscesses that are difficult to treat. Because of its capability to induce a rise of temperature at a very precise loc...

we investigated the effects of interaction between cotesia plutellae (kurdjumov) and bacillus thuringiensis berliner on parasitism and an immune effector (phenoloxidase activity) of a bt-susceptible and a bt-resistant population of plutella xylostella (linnaeus) in laboratory. parasitism success of c. plutellae varied depending on the use of b. thuringiensis or its toxin, and the timing of appl...

Despite the well-documented historical importance of polyploidy, the mechanisms responsible for the establishment and evolutionary success of novel polyploid lineages remain unresolved. One possibility, which has not been previously evaluated theoretically, is that novel polyploid lineages are initially more resistant to pathogens than the diploid progenitor species. Here, we explore this possi...

Pathogen infection is typically costly to hosts, resulting in reduced fitness. However, pathogen exposure may also come at a cost even if the host does not become infected. These fitness reductions, referred to as "resistance costs", are inducible physiological costs expressed as a result of a trade-off between resistance to a pathogen and aspects of host fitness (e.g., reproduction). Here, we ...

Background & Aims: Acinetobacter spp. are non-fermenting gram-negative coccobacilli that have emerged in recent three decades as major causes of nosocomial infections. Acinetobacter baumannii is the most common pathogen causing a wide spectrum of infections. Acinetobacter infections are difficult to treat, due to both the intrinsic resistance of the pathogen and its ability to readily acquire n...