Serum human chorionic gonadotropin measurement in the diagnosis of ectopic pregnancy when transvaginal sonography is inconclusive

Transition from placental to pulmonary oxygenation at birth depends on a rapid removal of fetal lung fluid from the developing alveoli. Alveolar fluid clearance was examined in ventilated, anesthetized developing guinea pigs of the ages newborn, 2-d-old, 5-d-old, 30-d-old, and 60-d-old (adult). An isosmolar 5% albumin solution was instilled into the lungs of the guinea pigs; the guinea pigs were then studied for 1 h. Alveolar fluid clearance was measured from the increase in alveolar protein concentration as water was reabsorbed. Newborn guinea pigs had a very high alveolar fluid clearance rate that declined rapidly within the first 5 postnatal days towards adult levels. The high alveolar fluid clearance at birth was apparently mediated by the beta-adrenergic system as demonstrated by the elevated plasma epinephrine levels and the increased sensitivity to inhibition by the beta-adrenergic antagonist propranolol immediately after birth. Surprisingly, exogenous addition of epinephrine was not able to stimulate alveolar fluid clearance in the newborn lung, but exogenous epinephrine stimulation increased over time to adult levels. The elevated alveolar fluid clearance at birth was associated with a significantly greater amiloride sensitivity in the newborn guinea pig lung. Northern blot analysis of distal lung tissue as well as isolated alveolar epithelial type II cells showed and confirmed higher levels of the alpha-subunit of the epithelial sodium channel mRNA in the newborn lung that rapidly tapered off toward adult levels. In conclusion, these data demonstrate the importance of the beta-adrenergic system and amiloride-sensitive sodium transporting pathways for clearance of fetal lung fluid at birth.     

Private business: the uptake of confidential HIV testing in remote aboriginal communities on the Anangu Pitjantjatjara Lands

Bacterial populations associated with three sample types from the neck region of poultry carcasses in the dirty area of an abattoir were characterized. Sample types before and after scalding were skin only, feathers only, and a skin and feather combination. The neck skin of carcasses after the defeathering processing stage was also sampled. Bacterial populations associated with water from the scald tank, rubber fingers at the exit of the defeathering machine, and air in the dirty area were also characterized. Bacterial colonies (751) were randomly isolated from yeast extract-supplemented tryptone soya agar plates exhibiting 30 to 300 colonies. Micrococcus spp. were isolated in the highest proportion from pre-and postscalded carcass samples (63.5 to 86.1% of isolates), regardless of the sample type. Conversely, Enterobacteriaceae (40.3%), Acinetobacter (19.4%), and Aeromonas/Vibrio (12.5%) species predominated on neck skin samples taken from mechanically defeathered carcasses. Isolates from the rubber fingers were, however, predominantly Micrococcus spp. (94.4%). Bacterial groups isolated in the highest proportion from scald tank water samples were Micrococcus spp. (38.3%), species of Enterobacteriaceae (29.1%), and lactic acid bacteria (17.0%). Corynebacterium spp., species of Enterobacteriaceae, and Micrococcus spp. were dominant on air settle plates.     

Reactive oxygen intermediates mediate a systemic signal network in the establishment of plant immunity

Recognition of an avirulent pathogen stimulates an oxidative burst generating O2- and H2O2, and these reactive oxygen intermediates (ROIs) cue the induction of defense genes and cell death in the development of a restricted lesion. This localized hypersensitive response (HR) is accompanied by the development of systemic acquired resistance to virulent pathogens. Here we show that inoculation of Arabidopsis leaves with avirulent Pseudomonas syringae induces secondary oxidative bursts in discrete cells in distant tissues, leading to low-frequency systemic micro-HRs. The primary oxidative burst induces these systemic responses, and both the primary burst and the secondary microbursts are required for systemic immunity. Hence, ROIs mediate a reiterative signal network underlying systemic as well as local resistance responses.     

Manipulating ruminal fermentation: a microbial ecological perspective

The essential role of ruminal microflora in ruminant nutrition provides the potential for improvement in animal production via altering the numbers or activities of specific classes of microorganisms. Successful alterations will be facilitated by an understanding of the microbial ecology of the rumen based on its mechanistic underpinnings. Demonstrated improvements in ruminal fermentation can be traced to their consonance with well-established principles of microbial ecology (niche occupancy, selective pressure, adaptation, and interactions) and the thermodynamics and kinetics of substrate utilization. Application of these principles to several proposed alterations of the ruminal bacterial population allows a prediction of their relative feasibility. Improving fiber digestion, decreasing protein degradation, and detoxifying feed components that are present in low concentrations will be difficult to achieve in the rumen and are best approached by altering the feed, either genetically or with postharvest treatment. By contrast, the detoxification of feed components present in high concentration, and redirection of electron disposal away from methanogenesis, are more productive targets for microbiological research.