Subject(s)
Cardiac Catheterization/adverse effects , Coronary Angiography/adverse effects , Endocarditis, Bacterial/etiology , Staphylococcal Infections/etiology , Staphylococcus/isolation & purification , Cefazolin/therapeutic use , Cephalosporins/therapeutic use , Endocarditis, Bacterial/drug therapy , Endocarditis, Bacterial/microbiology , Humans , Male , Middle Aged , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Staphylococcus/drug effectsABSTRACT
Urinary tract infections (UTIs) are still the precipitating cause for 7 million patient visits per year with total costs exceeding one billion dollars. Diagnostic modalities have become more "friendly" for the smaller laboratory with "dip stick" culture tests providing a rapid method of isolation of pathogens. In many cases, empiric therapy is more cost effective than culture in uncomplicated UTIs in women. The etiologic organisms implicated in UTIs have not changed dramatically over the past two decades, with E. coli still accounting for the majority of cases. Antibiotic susceptibility patterns have changed dramatically, with ampicillin losing utility die to the emergence of resistance. Quinolones, which have been exceedingly active against gram-negative enteric pathogens, are no longer universally active and more pathogenic organisms, such as pseudomonas, may be resistant. The emergence of other highly resistant organisms, such as Enterococcus faecium, must be watched for.
Subject(s)
Urinary Tract Infections/drug therapy , Acute Disease , Candidiasis/drug therapy , Female , Humans , Pyelonephritis/drug therapy , Recurrence , Risk Factors , Urinary Catheterization/adverse effects , Urinary Tract Infections/physiopathologyABSTRACT
Brush-border membrane vesicles from hamster intestine were employed to investigate uptake (binding) of vitamin B12 (B12). Ileal vesicles took up 25 times more B12 than did jejunal vesicles. Uptake of B12 by ileal vesicles was dependent on intrinsic factor (IF) and required Ca2+. Increasing the Ca2+ concentration caused an increase in uptake of B12 reaching a maximum at approximately 8 mM Ca2+. At high Ca2+ concentrations, 6-8 mM, Mg2+ had little effect on uptake of B12. At low Ca2+ concentrations, up to 2 mM, Mg2+ stimulated B12 uptake. Mg2+, Mn2+, and, to a lesser extent, Sr2+ stimulated Ca2+-dependent B12 uptake, but Zn2+, Ba2+, Na+, K+, and La3+ did not. B12 was apparently not metabolized and was bound as IF-B12 complex, which could be removed with (ethylenedinitrilo)tetraacetic acid (EDTA). Our results suggest that two types of divalent cation reactive sites are involved in binding of IF-B12. One is Ca2+ specific. The other is less specific reacting with Mg2+, Mn2+, Sr2+, and perhaps Ca2+ itself, thereby stimulating Ca2+-dependent binding of IF-B12 to its ileal receptor.
