Near-infrared system's efficiency for peripheral intravenous cannulation in a level III neonatal intensive care unit: a cross-sectional study.

Venipuncture is a painful and invasive procedure for hospitalised newborns and represents a challenge for neonatal healthcare professionals. This study evaluated the most efficient cannulation method based on the proportion of success at the first attempt, standard care or near-infrared (NIR) device use, and pain assessment. An observational study with two arms was conducted in the neonatal intensive care unit (NICU) of a tertiary-care university hospital in Italy. All newborns undergoing peripheral vein cannulation and only nurses with more than 5 years of professional experience in the NICU were eligible for the first arm. Only newborns with a body weight of >2500 g at cannulation and all nurses working in the NICU were involved in the second arm. In the first arm of the study, no statistically significant differences between the NIR and control groups were found in terms of proportion of successful at the first attempt 60.6% (confidence interval [CI] 95%: 48.8; 72.4) vs. 56.1% (CI 95%: 44.1; 68.0) and the mean premature infant pain profile score 6.3 (CI 95%: 5.4-7.1) vs. 5.8 (CI 95%: 5.0-6.6). In the second arm, only among less experienced nurses (<1 year), we observed a significant increase in the proportion of success in the NIR group compared with the control group, nearly tripling the success rate (72.7% [54.1; 91.3] vs. 23.1% [0.2; 46.0]).  Conclusion: This study reported no differences between the NIR and control groups. The results also suggest that using a NIR device may be advantageous for healthcare professionals with less experience during first-time cannulation. What is Known: • Venipuncture is a painful procedure commonly used to place a peripheral venous catheter for administering nutrients or drugs. • Near-infrared light facilitates the visualisation of veins and consequently, the performance of cannulation in the paediatric population. What is New: • The near-infrared light device was not associated with fewer attempts and a lower premature infant pain profile score in placing venous access in newborns than the traditional method. • The near-infrared light device could help nurses with less professional experience place a peripheral venous catheter.

Population genomic analyses of RAD sequences resolves the phylogenetic relationship of the lichen-forming fungal species Usneaantarctica and Usneaaurantiacoatra.

Neuropogonoid species in the lichen-forming fungal genus Usnea exhibit great morphological variation that can be misleading for delimitation of species. We specifically focused on the species delimitation of two closely-related, predominantly Antarctic species differing in the reproductive mode and representing a so-called species pair: the asexual U.antarctica and the sexual U.aurantiacoatra. Previous studies have revealed contradicting results. While multi-locus studies based on DNA sequence data provided evidence that these two taxa might be conspecific, microsatellite data suggested they represent distinct lineages. By using RADseq, we generated thousands of homologous markers to build a robust phylogeny of the two species. Furthermore, we successfully implemented these data in fine-scale population genomic analyses such as DAPC and fineRADstructure. Both Usnea species are readily delimited in phylogenetic inferences and, therefore, the hypothesis that both species are conspecific was rejected. Population genomic analyses also strongly confirmed separated genomes and, additionally, showed different levels of co-ancestry and substructure within each species. Lower co-ancestry in the asexual U.antarctica than in the sexual U.aurantiacoatra may be derived from a wider distributional range of the former species. Our results demonstrate the utility of this RADseq method in tracing population dynamics of lichens in future analyses.

The use of microsatellite markers for species delimitation in Antarctic Usnea subgenus Neuropogon.

Lichens are symbiotic associations consisting of a fungal (mycobiont) and one or more photosynthetic (photobionts) partners and are the dominant component, and most important primary producers, of Antarctic terrestrial ecosystems. The most common lichens in the maritime Antarctic are Usnea antarctica and U. aurantiacoatra, a so-called "species pair" in which U. antarctica shows asexual reproduction and propagation via soredia and U. aurantiacoatra forms ascospores in apothecia. Previous molecular analyses were not able to unambiguously distinguish the two morphotypes as species. Therefore, the goal of this study was to find out whether fast-evolving SSR (single sequence repeat) markers are able to separate morphotypes more clearly and help to clarify their taxonomy. We investigate 190 individuals from five mixed stands of both morphotypes collected in King George Island and Elephant Island (South Shetland Islands, Antarctica). Based on 23 microsatellite markers designed from sequenced genomes, discriminant analysis of principal components (DAPC), Bayesian clustering analysis, and coalescent-based estimation of gene flow show clear evidence for the existence of two different species distinguishable by reproductive mode. We did not detect any statistical association between genetic clusters and three previously reported chemical races of each species.

Fungus-specific SSR markers in the Antarctic lichens Usnea antarctica and U. aurantiacoatra (Parmeliaceae, Ascomycota).

PREMISE OF THE STUDY: Usnea antarctica and U. aurantiacoatra (Parmeliaceae) are common lichens in the maritime Antarctic. These species share the same habitats on King George Island (South Shetland Islands, Antarctica) and are distinguishable based on reproductive strategies. METHODS AND RESULTS: We developed 23 fungus-specific simple sequence repeat (SSR) markers that cross-amplify between the two species. We used a low-coverage genome-skimming approach on one sample of each species to identify SSR repeats in the two species. Primers were designed for 3-4-bp repeats, and only the loci common to both species were selected for further analyses. Seventy-seven samples of the two species were selected to assess fungal specificity, genetic variability, and linkage of the markers. In addition, we tested cross-amplification in other Usnea species. CONCLUSIONS: The 23 newly designed SSR markers are suitable for population genetic and phylogeographic studies of Usnea species.

Selection processes in simple sequence repeats suggest a correlation with their genomic location: insights from a fungal model system.

BACKGROUND: Adaptive processes shape the evolution of genomes and the diverse functions of different genomic regions are likely to have an impact on the trajectory and outcome of this evolution. The main underlying hypothesis of this study is that the evolution of Simple Sequence Repeats (SSRs) is correlated with the evolution of the genomic region in which they are located, resulting in differences of motif size, number of repeats, and levels of polymorphisms. These differences should be clearly detectable when analyzing the frequency and type of SSRs within the genome of a species, when studying populations within a species, and when comparing closely related sister taxa. By coupling a genome-wide SSR survey in the genome of the plant pathogenic fungus Heterobasidion irregulare with an analysis of intra- and interspecific variability of 39 SSR markers in five populations of the two sibling species H. irregulare and H. annosum, we investigated mechanisms of evolution of SSRs. RESULTS: Results showed a clear dominance of trirepeats and a selection against other repeat number, i.e. di- and tetranucleotides, both in regions inside Open Reading Frames (ORFs) and upstream 5' untranslated region (5'UTR). Locus per locus AMOVA showed SSRs both inside ORFs and upstream 5'UTR were more conserved within species compared to SSRs in other genomic regions, suggesting their evolution is constrained by the functions of the regions they are in. Principal coordinates analysis (PCoA) indicated that even if SSRs inside ORFs were less polymorphic than those in intergenic regions, they were more powerful in differentiating species. These findings indicate SSRs evolution undergoes a directional selection pressure comparable to that of the ORFs they interrupt and to that of regions involved in regulatory functions. CONCLUSIONS: Our work linked the variation and the type of SSRs with regions upstream 5'UTR, putatively harbouring regulatory elements, and shows that the evolution of SSRs might be affected by their location in the genome. Additionally, this study provides a first glimpse on a possible molecular basis for fast adaptation to the environment mediated by SSRs.