Glucagon Receptor Antagonism Improves Glucose Metabolism and Cardiac Function by Promoting AMP-Mediated Protein Kinase in Diabetic Mice

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Diverse Brain Myeloid Expression Profiles Reveal Distinct Microglial Activation States and Aspects of Alzheimer’s Disease Not Evident in Mouse Models

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Enhanced Butanol Production by Clostridium beijerinckii BA101 Grown in Semidefined P2 Medium Containing 6 Percent Maltodextrin or Glucose

Dramatically elevated levels of butanol and acetone resulted in higher butanol and total solvent yields for hyperamylolytic Clostridium beijerinckii BA101 relative to the NCIMB 8052 parent strain grown in semidefined P2 medium containing either 6% glucose or STAR-DRI 5 maltodextrin. C. beijerinckii BA101 consistently produced on the order of 19 g of butanol per liter in 20-liter batch fermentations. This represents a greater than 100% increase in butanol concentration by the BA101 strain compared to the parent NCIMB 8052 strain. The kinetics of butanol production over time also indicate a more rapid rate of butanol production by BA101 in semidefined P2 medium containing glucose or maltodextrin. The lower levels of butyric and acetic acids produced over the course of the fermentation carried out by BA101 are consistent with an enhanced capacity for uptake and recycling of these acids. C. beijerinckii BA101 appears to more completely utilize carbohydrate compared to the 8052 strain. Carbon balance following fermentation by C. beijerinckii 8052 and BA101 indicates that sufficient carbon is available for the twofold increase in butanol concentration observed during BA101 fermentations. C. beijerinckii BA101 also has superior solvent production capacity during continuous culture fermentation in P2 medium containing 6% glucose. Volumetric solvent yields of 0.78 and 1.74 g/liter/h for BA101 and 0.34 and 1.17 g/liter/h for NCIMB 8052 were obtained at dilution rates of 0.05 and 0.20 h(sup-1), respectively. No drift towards acid synthesis (strain degeneration) was observed for up to 200 h (d = 0.05 h(sup-1)) and 100 h (d = 0.20 h(sup-1)).     

An Analysis of the Self of the Western Physician: A Study on the Evolution of Homo Hippocratus

This paper is about western physicians in general, andthe Israeli variant in particular. The theoretical focuswill be on the nature and dynamics of the medicalprofessional self within this interplay between thecultural concepts of universality and difference. Thediscussion will address the genesis of this professionalself and the implications of its extraordinary strengthand tenacity, which has endured for centuries indifferent local contexts wherever western medicine hasexisted. The impetus for this study is the subduedrumbling which is echoing throughout the professionsuggesting that this self is no longer the Rock ofGibraltar that it seemed in the past.     

Multiple-Antibiotic Resistance of Enterococcus spp. Isolated from Commercial Poultry Production Environments

The potential impact of food animals in the production environment on the bacterial population as a result of antimicrobial drug use for growth enhancement continues to be a cause for concern. Enterococci from 82 farms within a poultry production region on the eastern seaboard were isolated to establish a baseline of susceptibility profiles for a number of antimicrobials used in production as well as clinical environments. Of the 541 isolates recovered, Enterococcus faecalis (53%) and E. faecium (31%) were the predominant species, while multiresistant antimicrobial phenotypes were observed among all species. The prevalence of resistance among isolates of E. faecalis was comparatively higher among lincosamide, macrolide, and tetracycline antimicrobials, while isolates of E. faecium were observed to be more frequently resistant to fluoroquinolones and penicillins. Notably, 63% of the E. faecium isolates were resistant to the streptogramin quinupristin-dalfopristin, while high-level gentamicin resistance was observed only among the E. faecalis population, of which 7% of the isolates were resistant. The primary observations are that enterococci can be frequently isolated from the poultry production environment and can be multiresistant to antimicrobials used in human medicine. The high frequency with which resistant enterococci are isolated from this environment suggests that these organisms might be useful as sentinels to monitor the development of resistance resulting from the usage of antimicrobial agents in animal production.     

THE FUNCTION OF CALL ALTERNATION IN ANURAN AMPHIBIANS: A TEST OF THREE HYPOTHESES

Males of many species of anurans alternate calls with those of their neighbors in a chorus. This pattern of calling reduces signal interference and may: 1) facilitate intermale spacing because males can better gauge the intensity of neighbors' calls if these calls do not overlap with their own; 2) help preserve species-specific temporal information in calls required to attract females; and/or 3) make it easier for females to localize males in the chorus. I tested these hypotheses with three species that exhibit call alternation, Hyla crucifer, H. versicolor, and H. microcephala. Males of all three species gave more aggressive calls to high-intensity synthetic stimuli that alternated with their calls than to those that overlapped their calls. These results support the first hypothesis. Results of four-speaker female choice experiments using alternating and overlapping calls indicate that preservation of signal integrity also is important in H. versicolor and H. microcephala, species that have fine-scale temporal information in their calls. However, the third hypothesis was not supported; females failed to discriminate among alternating and overlapping calls if the problem of signal disruption was eliminated or irrelevant.