Lactobacilli, principally the strains that are hydrogen peroxide (H 2 O 2 ) producing, may have a protective effect against vaginal colonization by pathogenic species such as those that cause bacterial vaginosis. Previous reports have also suggested that H 2 O 2 -producing lactobacilli in the vagina may protect pregnant women against ascending infection of the chorioamniotic membranes and uterine cavity. We report the identification and H 2 O 2 production of lactobacilli isolated from vaginal swabs collected at 20 weeks' gestation from a population of pregnant women at high risk of preterm birth. We also report the correlation between identification and H 2 O 2 production in relation to the outcomes of chorioamnionitis and preterm birth. Lactobacilli were identified by partial 16S rRNA gene sequencing. H 2 O 2 production by isolates was determined by a semiquantitative method. The most commonly isolated species were L. crispatus, L. gasseri, L. vaginalis and L. jensenii. Amounts of H 2 O 2 produced by lactobacilli varied widely. The presence of lactobacilli producing high levels of H 2 O 2 in the vagina of this population of pregnant women was associated with a reduced risk of bacterial vaginosis at 20 weeks' gestation and subsequent chorioamnionitis. L. jensenii and L. vaginalis produced the highest levels of H 2 O 2 . We postulate that H 2 O 2 -producing lactobacilli are able to reduce the incidence of ascending infections of the uterus and the subsequent production of proinflammatory molecules which are important in the pathogenesis of chorioamnionitis and preterm birth.The adult human vagina is a complex ecosystem containing an abundance of microorganisms. In women of childbearing age this system is dominated by Lactobacillus spp., a genus of gram-positive, nonmotile rod-like bacteria, a defining characteristic of which is the ability to grow in acid media and tolerate acid conditions (pH Ͻ 4.5); lactobacilli also ferment carbohydrates to produce lactic acid. In bacterial vaginosis (BV) the balance of flora is changed with reduced numbers of lactobacilli and an increase in numbers of other facultative and anaerobic species such as anaerobic cocci Prevotella spp., Gardnerella vaginalis, and Mobiluncus spp. BV is associated with a number of poor health outcomes, including preterm birth (31). Lactobacilli, principally the strains that are H 2 O 2 producing, may have a protective effect against vaginal colonization by pathogenic species such as those that cause BV (16) and possibly human immunodeficiency virus and gonorrhoea (26). Previous reports have also suggested that H 2 O 2 -producing lactobacilli in the vagina may protect pregnant women against ascending infection of the chorioamniotic membranes and uterine cavity (12, 18). There have been few studies in which lactobacilli have been identified to species level and in which H 2 O 2 production in pregnant women has been determined. We report the identification and H 2 O 2 production of lactobacilli isolated from vaginal swabs collected at 20 weeks' gestatio...

This outbreak was controlled by emphasizing the control of environmental reservoirs and did not require recourse to ward closure or placement of affected patients in isolation.

F Fo oe et ta al l aai ir rw wa ay y m mo ot to or r t to on ne e i in n p pr re en na at ta al l l lu un ng g d de ev ve el lo op pm me en nt t o of f t th he e p pi ig g We speculate that the bronchomotor tone and associated spontaneous activity, which move the lung fluid along the airways, serve to maintain an even positive pressure in localized areas of the bronchial tree which is essential to provide the stimulus for continued growth of the lung.

Many central vascular catheters (CVCs) are removed unnecessarily because current diagnostic methods for CVC-associated infection are unreliable. A quantitative PCR assay using primers and probe targeted to bacterial 16S ribosomal DNA was used to measure the levels of bacterial DNA in blood samples drawn through the CVC in a population of patients receiving intravenous nutrition. Bacterial DNA concentrations were raised in 16 of 16 blood samples taken during episodes of probable bacterial CVC-associated infection. Bacterial DNA concentrations were raised in 4 of 29 episodes in which bacterial CVC-associated infection was unlikely. The use of this technique has the potential to substantially reduce the unnecessary removal of CVCs.In many patient populations, central vascular catheters (CVCs) are routinely used for the administration of drugs, fluids, or intravenous feeding solutions. CVCs are a major risk factor for bloodstream infections. The majority of hospitalacquired bloodstream infections are associated with the use of a CVC (3). These infections are associated with considerable costs for patients and health providers.CVC infection is caused predominantly by bacteria, particularly staphylococci, with a small proportion of infections being attributable to fungi. Staphylococcus epidermidis is the most common cause of CVC-associated bacteremia. CVC infections caused by S. epidermidis can often be effectively treated with antibiotics infused through or locked in to the CVC (4, 15). Many of the other bacterial and fungal causes of infection respond poorly to antibiotic therapy alone, and patient outcome is improved by removal of the CVC.Traditional methods of diagnosis of CVC-associated infection rely on clinical features and quantitative microbiology of blood samples (15) or on methods that can only be applied following CVC removal. The clinical features of CVC infection may be nonspecific, particularly in patients undergoing intensive care or in patients who are immunocompromised. A number of novel methods for the diagnosis of CVC infection have been proposed (1, 2, 4, 7-10). These methods have not been widely adopted, either because of poor performance in some groups of patients, such as those on antibiotics, or because of a requirement for invasive sampling of the CVC. Blot et al. (2) described a method that compared the differential times to positivity, as determined by a continuous automated blood culture monitoring system which compares the growth rates of organisms in blood collected from the catheter and a peripheral vein. Another method involves culture from the terminal 4-cm segment of the cannula, which is rolled over the entire surface of an agar plate five times, and counting of the resultant colonies (9, 12). However, interpreting the significance of the resultant growth may be problematic (9). In addition, quantitative microbiology is unreliable for patients exposed to antibiotics, so even with appropriate use of diagnostic methods there often remains considerable diagnostic uncertainty. As a resu...

We investigated whether the airways of the lungs from 8 to 10 g fetal pigs (the pseudoglandular phase) have a nerve supply, are functionally innervated and narrow in response to electrical field stimulation and to agonists. Measurements of airway narrowing were made by real-time video imaging of intact isolated bronchial tree freed of associated parenchyma and vasculature. The distal (100 to 300 microns lumen diameter) and terminal (approximately 25 to 50 microns lumen diameter) airways narrowed strongly to acetylcholine and histamine, to within 50 to 80 microns of the base of the epithelial buds. Electrical field stimulation produced rapid narrowing followed by relaxation, and responses were blocked by atropine and tetrodotoxin, indicating a functional cholinergic innervation. Transient periods (3 to 5 min) of spontaneous narrowing were seen in localized regions of the bronchial tree which moved the lung liquid to and fro. An extensive nerve supply to the bronchial tree was seen after immunocytochemical staining of tissue whole mounts with anti-neurofilament. Nerves supplied the distal and terminal airways with fine branches penetrating the smooth muscle of the airway wall. A few fibers extended to the growing edge of the smooth muscle at the very base of the epithelial bud. The smooth muscle was cylindrically arranged around the airway wall all the way to the epithelial bud. We propose that onset of function of smooth muscle and its innervation occurs shortly after differentiation of the smooth muscle at the growing tips of the airways.