ABSTRACT
Serratia marcescens is a recognized cause of outbreaks in neonatal intensive care units (NICUs). The aim of the present study was to investigate two nosocomial outbreaks of S. marcescens that occurred in an NICU in Northern Italy. In order to determine the origin of the outbreaks and the associated morbidity and mortality of S. marcescens infections and epidemiological investigation was established including molecular typing of the isolates. Containment of the outbreaks was achieved by means of strict hygienic measure and cohort nursing of the infected and/or colonized infants. We experimented with the use of probiotics as an infection control measure.
Subject(s)
Cross Infection/epidemiology , Infection Control/organization & administration , Serratia Infections/epidemiology , Serratia marcescens/isolation & purification , Birth Weight , Cross Infection/prevention & control , Disease Outbreaks , Electrophoresis, Gel, Pulsed-Field , Female , Gestational Age , Humans , Infant , Infant, Newborn , Intensive Care Units, Neonatal , Italy/epidemiology , Male , Probiotics/therapeutic use , Serratia Infections/microbiology , Serratia Infections/prevention & controlABSTRACT
A high calcium-requiring protease was purified from the hearts of myopathic hamsters. The biochemical properties of the enzyme were studied with [3H]acetylcasein as substrate. Comparison of the enzyme from hamster and rat hearts indicated no species specificity. Increased levels of the enzyme were associated with the development of cardiac lesions in myopathic hamsters.
Subject(s)
Calpain/metabolism , Cardiomyopathies/enzymology , Animals , Calcium/pharmacology , Calpain/antagonists & inhibitors , Calpain/isolation & purification , Cricetinae , Mesocricetus , Myocardium/enzymology , Rats , Species SpecificityABSTRACT
Two distinct Ca2+-activated proteinases were purified and characterized from hearts of hypertensive rats. Ca2+-activated proteinases I and II, having low and high Ca2+ requirements, respectively, were first separated by DEAE-cellulose chromatography. The enzymes were then purified individually by different column procedures: chromatography on phenyl-Sepharose, then Sephadex G-200 for proteinase I and reactive-red agarose for proteinase II. The apparent molecular weight of purified proteinase I was 125 000 and that for purified proteinase II was 110 000. Both enzymes are heterodimers made up of a larger catalytic subunit and a smaller subunit devoid of proteinase activity. Ca2+ concentrations for half-maximal activation were 5 microM for proteinase I and 200 microM for proteinase II. Both enzymes were inhibited by sulfhydryl-modifying agents, but exhibited different characteristics in the auto-digestion reaction in the presence of Ca2+. Proteinases I and II were also purified from hearts of normotensive rats and shown to be identical to their respective counterparts from hearts of hypertensive rats. However, proteinase II activity in hypertensive rat hearts was significantly elevated as compared to controls.
