Outcomes of daytime nurse practitioner-staffed versus resident-staffed nonsurgical intensive care units: A retrospective observational study.

BACKGROUND: Rapid developments in medical care-such as monitoring devices, medications, and working hours restrictions for intensive care personnel-have dramatically increased the demand for intensive care physicians. Therefore, nurse practitioner (NP)-staffed care is becoming increasingly important. This study was aimed to compare the outcomes of daytime NP-staffed and daytime resident-staffed nonsurgical intensive care units (ICU). METHODS: We retrospectively assessed patients admitted to a nonsurgical ICU from March 2017 to December 2017. We collected basic patient data, including age, sex, admission diagnosis, transferring unit, and Acute Physiology and Chronic Health Evaluation II (APACHE II) score. Primary endpoints were ICU mortality, hospital mortality, and 30-day mortality. Secondary endpoints were 48-h readmission, discharge to nonhome locations, and lengths of ICU and hospital stay. RESULTS: A total of 838 subjects were analysed: 334 subjects in the NP-staffed group and 504 in the resident-staffed group. The NP-staffed group was more likely to come from inpatient units (38.3% vs 16.5% for resident-staffed group; p < 0.001) and had lower disease severity (APACHE II score, 13.9 ± 8.4 vs 15.1 ± 8.2 for resident-staffed group; p = 0.047). After adjusting for age, sex, location before ICU admission, APACHE II score, and significantly different basic characteristics, there were no differences in ICU mortality, hospital mortality, or 30-day mortality between the two groups. Secondary analysis showed the NP-staffed group had a lower discharge rate to nonhome locations (2.1% vs 6.3%; p = 0.023) and shorter hospital stay (12.1 ± 14.1 vs 14.2 ± 14.3 days; p = 0.015). CONCLUSIONS: We observed no difference in mortality between daytime NP-staffed and resident-staffed nonsurgical ICUs. Daytime NP-staffed care is an effective, safe, feasible method for staffing nonsurgical ICUs.

Historic Mining and Agriculture as Indicators of Occurrence and Abundance of Widespread Invasive Plant Species.

Anthropogenic disturbances often change ecological communities and provide opportunities for non-native species invasion. Understanding the impacts of disturbances on species invasion is therefore crucial for invasive species management. We used generalized linear mixed effects models to explore the influence of land-use history and distance to roads on the occurrence and abundance of two invasive plant species (Rosa multiflora and Berberis thunbergii) in a 900-ha deciduous forest in the eastern U.S.A., the Powdermill Nature Reserve. Although much of the reserve has been continuously forested since at least 1939, aerial photos revealed a variety of land-uses since then including agriculture, mining, logging, and development. By 2008, both R. multiflora and B. thunbergii were widespread throughout the reserve (occurring in 24% and 13% of 4417 10-m diameter regularly-placed vegetation plots, respectively) with occurrence and abundance of each varying significantly with land-use history. Rosa multiflora was more likely to occur in historically farmed, mined, logged or developed plots than in plots that remained forested, (log odds of 1.8 to 3.0); Berberis thunbergii was more likely to occur in plots with agricultural, mining, or logging history than in plots without disturbance (log odds of 1.4 to 2.1). Mining, logging, and agriculture increased the probability that R. multiflora had >10% cover while only past agriculture was related to cover of B. thunbergii. Proximity to roads was positively correlated with the occurrence of R. multiflora (a 0.26 increase in the log odds for every 1-m closer) but not B. thunbergii, and roads had no impact on the abundance of either species. Our results indicated that a wide variety of disturbances may aid the introduction of invasive species into new habitats, while high-impact disturbances such as agriculture and mining increase the likelihood of high abundance post-introduction.

Genetic and physiological data suggest demographic and adaptive responses in complex interactions between populations of figs (Ficus pumila) and their pollinating wasps (Wiebesia pumilae).

To study interactions between host figs and their pollinating wasps and the influence of climatic change on their genetic structures, we sequenced cytoplasmic and nuclear genes and genotyped nuclear microsatellite loci from two varieties of Ficus pumila, the widespread creeping fig and endemic jelly fig, and from their pollinating wasps, Wiebesia pumilae, found in Taiwan and on nearby offshore islands. Great divergence in the mitochondrial cytochrome c oxidase subunit I (mtCOI) with no genetic admixture in nuclear markers indicated that creeping- and jelly-fig wasps are genetically distinct. Compared with creeping-fig wasps, jelly-fig wasps also showed better resistance under cold (20 °C) than warm (25 and 30 °C) conditions in a survival test, indicating their adaptation to a cold environment, which may have facilitated population expansion during the ice age as shown by a nuclear intron and 10 microsatellite loci. An excess of amino acid divergence and a pattern of too many rare mtCOI variants of jelly-fig wasps as revealed by computer simulations and neutrality tests implied the effect of positive selection, which we hypothesize was associated with the cold-adaptation process. Chloroplast DNA of the two fig plants was completely segregated, with signs of genetic admixture in nuclear markers. As creeping- and jelly-fig wasps can pollinate creeping figs, occasional gene flow between the two figs is thus possible. Therefore, it is suggested that pollinating wasps may be playing an active role in driving introgression between different types of host fig.

Distinct hepatitis B virus dynamics in the immunotolerant and early immunoclearance phases.

Little is known about hepatitis B virus (HBV) diversity changes within a host during the immunotolerant phase of chronic HBV infection. Such knowledge, nevertheless, may help in understanding how host immunity and HBV interact at the early stage of infection. In this study, serial serum samples were collected from a long-term (>17 years) follow-up cohort of seven patients, and multiple copies of the full-length viral genome from serially sampled sera were recovered and analyzed. Viral genetic diversity was positively correlated with host immunity, represented by levels of alanine aminotransferase (ALT), but was negatively correlated with the viral copy number. During the immunotolerant phase, when the host immunity was feeble (ALT < 20 U/liter), viral nucleotide diversity decreased while copy numbers increased. Rates of evolutionary change derived for different patients were in a very narrow range (1.6 x 10(-5) to 5.4 x 10(-5)/site/year). As the disease progressed toward the immunoclearance phase (ALT > 20 U/liter), viral diversity increased but copy numbers decreased. Evolutionary rates varied among patients in accordance with their levels of ALT, ranging from 9.6 x 10(-6) to 3.2 x 10(-4)/site/year. More than half (19/32 sites) of positively selected sites resided in immune epitopes, suggesting their possible role in host immunity. Our results demonstrate that host immunity is a dominant factor in HBV evolution. Different selective forces, including immune-mediated positive selection and virus-mediated negative selection, operate in tandem in shaping viral population dynamics within a host.