Incubation

About: Incubation is a research topic. Over the lifetime, 5748 publications have been published within this topic receiving 126541 citations.

Female nutritional state affects the rate of male incubation feeding in the pied flycatcher Ficedula hypoleuca

Abstract: Male pied flycatches Ficedula hypoleuca regularly feed their mates during incubation. By experimentally supplying some females with extra food we studied how the female's nutritional state affected her incubation schedule and the rate at which her mate fed her. Females that received extra food spent more time on the nest and shorter periods away from it, compared with control females. This suggests that nest attentiveness is governed by the amount of energy available to the female. When females reccived extra food, males decreased their rate of incubation feeding. They also did so in response to increasing ambient temperatures, whereas incubation schedules were unaffected. We, therefore, conclude that our results support the “female nutrition hypothesis”, i.e., that the food provided by the male constitutes a significant nutritional contribution to the incubating female.

The incubation period during the pandemic of COVID-19: a systematic review and meta-analysis.

Abstract: The aim of our study was to determine through a systematic review and meta-analysis the incubation period of COVID-19. It was conducted based on the preferred reporting items for systematic reviews and meta-analyses (PRISMA). Criteria for eligibility were all published population-based primary literature in PubMed interface and the Science Direct, dealing with incubation period of COVID-19, written in English, since December 2019 to December 2020. We estimated the mean of the incubation period using meta-analysis, taking into account between-study heterogeneity, and the analysis with moderator variables. This review included 42 studies done predominantly in China. The mean and median incubation period were of maximum 8 days and 12 days respectively. In various parametric models, the 95th percentiles were in the range 10.3–16 days. The highest 99th percentile would be as long as 20.4 days. Out of the 10 included studies in the meta-analysis, 8 were conducted in China, 1 in Singapore, and 1 in Argentina. The pooled mean incubation period was 6.2 (95% CI 5.4, 7.0) days. The heterogeneity (I2 77.1%; p < 0.001) was decreased when we included the study quality and the method of calculation used as moderator variables (I2 0%). The mean incubation period ranged from 5.2 (95% CI 4.4 to 5.9) to 6.65 days (95% CI 6.0 to 7.2). This work provides additional evidence of incubation period for COVID-19 and showed that it is prudent not to dismiss the possibility of incubation periods up to 14 days at this stage of the epidemic.

Azithromycin impact on neutrophil oxidative metabolism depends on exposure time.

Abstract: Several antimicrobial agents have already been investigated relating to their influence on neutrophil ROS generation. Azithromycin provides, a dose-related anti-oxidant effect, after 15 min incubation, with the stimulating agent FMLP, as well with PMA or S. aureus. This finding was however obtained with concentrations not considered in therapeutics. Since short incubation times are not representative of the physiological situation, and since azithromycin is characterized by prolonged high concentrations within phagocytes, the same experiments were performed over 2 and 4 h exposures. A time-dependent anti-oxidant effect was then reported. The maximum effect was obtained with PMA (IC50 were 856 and 30 micrograms/ml for 15 min and 4 h incubation times respectively). Time-dependent modifications of neutrophil oxidative metabolism seem to be correlated with intracellular concentrations. Depressed oxidative metabolism might be related neither to azithromycin cellular toxicity, nor to superoxide scavenging properties. By increasing exposure periods, therapeutic concentrations could therefore lead to an anti-inflammatory effect, potentially of clinical interest since associated with bacteriostatic activity.

Rapid determination of antimicrobial susceptibility for urgent clinical situations.

Abstract: With conventional methods, results of antimicrobic susceptibility tests are not available until 2 to 3 days after the specimen is collected. Many clinical situations would benefit if results of susceptibility tests were available sooner. Information can be obtained more quickly by inoculating the test plates directly with clinical material such as exudate or urine. Data to show that this approach is too unreliable for clinical use, especially with specimens containing mixtures of microorganisms, are presented. Isolated colonies may be tested by means of a standardized disk diffusion method, but this requires an additional 18 to 24 hr. Faster results can be obtained by observing the test plates after incubation for only 5 to 6 hr. Such early zone measurements were compared with those obtained with the more conventional 16 to 18 hr. period of incubation. With the majority of drugs and bacterial genera, zones measured after a few hours are not altered with further incubation, but with certain genera and with certain drugs, the early preliminary readings are predictably unreliable, e.g., Enterobacter with ampicillin or cephalothin and Serratia with polymyxin B, both of which appear susceptible after incubation for 5 to 6 hr. but resistant after incubation overnight.