Chronological incongruences between mitochondrial and nuclear phylogenies of Aedes mosquitoes

3openInternationalOne-third of all mosquitoes belong to the Aedini, a tribe comprising common vectors of viral zoonoses such as Aedes aegypti and Aedes albopictus. To improve our understanding of their evolution, we present an updated multigene estimate of Aedini phylogeny and divergence, focusing on the disentanglement between nuclear and mitochondrial phylogenetic signals. We first show that there are some phylogenetic discrepancies between nuclear and mitochondrial markers which may be caused by wrong taxa assignment in samples collections or by some stochastic effect due to small gene samples. We indeed show that the concatenated dataset is model and framework dependent, indicating a general paucity of signal. Our Bayesian calibrated divergence estimates point toward a mosquito radiation in the mid-Jurassic and an Aedes radiation from the mid-Cretaceous on. We observe, however a strong chronological incongruence between mitochondrial and nuclear data, the latter providing divergence times within the Aedini significantly younger than the former. We show that this incongruence is consistent over different datasets and taxon sampling and that may be explained by either peculiar evolutionary event such as different levels of saturation in certain lineages or a past history of hybridization throughout the genus. Overall, our updated picture of Aedini phylogeny, reveal a strong nuclear-mitochondrial incongruence which may be of help in setting the research agenda for future phylogenomic studies of Aedini mosquitoesopenZadra, Nicola; Rizzoli, Annapaola; Rota-Stabelli, OmarZadra, N.; Rizzoli, A.; Rota-Stabelli, O

Management of spastic equinovarus foot in children with cerebral palsy: an evaluation of anatomical landmarks for selective nerve blocks of the tibial nerve motor branches

Objective: To define the anatomical landmarks of tibial motor nerve branches for selective motor nerve blocks of the gastrocnemii,  soleus and tibialis posterior muscles in the management of spastic equinovarus foot. Design: Observational study. Patients: Twenty-four children with cerebral palsy with spastic equinovarus foot. Methods: Considering the affected leg length, motor nerve branches to the gastrocnemii, soleus and tibialis posterior muscles were tracked using ultrasonography, and located in the space (vertical, horizontal, deep) according to the position of fibular head (proximal/distal) and a virtual line from the middle of popliteal fossa to the Achilles tendon insertion (medial/lateral). Results: Location of motor branches was defined as percentage of the affected leg length. Mean coordinates were: for the gastrocnemius medialis 2.5 ± 1.2% vertical (proximal), 1.0 ± 0.7% horizontal (medial), 1.5 ± 0.4% deep; for the gastrocnemius lateralis 2.3 ± 1.4% vertical (proximal), 1.1 ± 0.9% horizontal (lateral), 1.6 ± 0.4% deep; for the soleus 2.1 ± 0.9% vertical (distal), 0.9 ± 0.7% horizontal (lateral), 2.2 ± 0.6% deep; for the tibialis posterior 2.6 ± 1.2% vertical (distal), 1.3 ± 1.1% horizontal (lateral), 3.0 ± 0.7% deep. Conclusion: These findings may help the identification of tibial motor nerve branches to perform selective nerve blocks in patients with cerebral palsy with spastic equinovarus foot

Phylogenomic proof of Recurrent Demipolyploidization and Evolutionary Stalling of the “Triploid Bridge” in Arundo (Poaceae)

Polyploidization is a frequent phenomenon in plants, which entails the increase from one generation to the next by multiples of the haploid number of chromosomes. While tetraploidization is arguably the most common and stable outcome of polyploidization, over evolutionary time triploids often constitute only a transient phase, or a “triploid bridge”, between diploid and tetraploid levels. In this study, we reconstructed in a robust phylogenomic and statistical framework the evolutionary history of polyploidization in Arundo, a small genus from the Poaceae family with promising biomass, bioenergy and phytoremediation species. Through the obtainment of 10 novel leaf transcriptomes for Arundo and outgroup species, our results prove that recurrent demiduplication has likely been a major driver of evolution in this species-poor genus. Molecular dating further demonstrates that the species originating by demiduplication stalled in the “triploid bridge” for evolutionary times in the order of millions of years without undergoing tetratploidization. Nevertheless, we found signatures of molecular evolution highlighting some of the processes that accompanied the genus radiation. Our results clarify the complex nature of Arundo evolution and are valuable for future gene functional validation as well as reverse and comparative genomics efforts in the Arundo genus and other Arundinoideae

Phylogenomic proof of Recurrent Demipolyploidization and Evolutionary Stalling of the “Triploid Bridge” in Arundo (Poaceae)

Polyploidization is a frequent phenomenon in plants, which entails the increase from one generation to the next by multiples of the haploid number of chromosomes. While tetraploidization is arguably the most common and stable outcome of polyploidization, over evolutionary time triploids often constitute only a transient phase, or a “triploid bridge”, between diploid and tetraploid levels. In this study, we reconstructed in a robust phylogenomic and statistical framework the evolutionary history of polyploidization in Arundo, a small genus from the Poaceae family with promising biomass, bioenergy and phytoremediation species. Through the obtainment of 10 novel leaf transcriptomes for Arundo and outgroup species, our results prove that recurrent demiduplication has likely been a major driver of evolution in this species-poor genus. Molecular dating further demonstrates that the species originating by demiduplication stalled in the “triploid bridge” for evolutionary times in the order of millions of years without undergoing tetratploidization. Nevertheless, we found signatures of molecular evolution highlighting some of the processes that accompanied the genus radiation. Our results clarify the complex nature of Arundo evolution and are valuable for future gene functional validation as well as reverse and comparative genomics efforts in the Arundo genus and other Arundinoideae

Evolutionary Relationships of Ljungan Virus Variants Circulating in Multi-Host Systems across Europe

The picornavirus named ‘Ljungan virus’ (LV, species Parechovirus B) has been detected in a dozen small mammal species from across Europe, but detailed information on its genetic diversity and host specificity is lacking. Here, we analyze the evolutionary relationships of LV variants circulating in free-living mammal populations by comparing the phylogenetics of the VP1 region (encoding the capsid protein and associated with LV serotype) and the 3Dpol region (encoding the RNA polymerase) from 24 LV RNA-positive animals and a fragment of the 5′ untranslated region (UTR) sequence (used for defining strains) in sympatric small mammals. We define three new VP1 genotypes: two in bank voles (Myodes glareolus) (genotype 8 from Finland, Sweden, France, and Italy, and genotype 9 from France and Italy) and one in field voles (Microtus arvalis) (genotype 7 from Finland). There are several other indications that LV variants are host-specific, at least in parts of their range. Our results suggest that LV evolution is rapid, ongoing and affected by genetic drift, purifying selection, spillover and host evolutionary history. Although recent studies suggest that LV does not have zoonotic potential, its widespread geographical and host distribution in natural populations of well-characterized small mammals could make it useful as a model for studying RNA virus evolution and transmission

Evolutionary Relationships of Ljungan Virus Variants Circulating in Multi-Host Systems across Europe

The picornavirus named ‘Ljungan virus’ (LV, species Parechovirus B) has been detected in a dozen small mammal species from across Europe, but detailed information on its genetic diversity and host specificity is lacking. Here, we analyze the evolutionary relationships of LV variants circulating in free-living mammal populations by comparing the phylogenetics of the VP1 region (encoding the capsid protein and associated with LV serotype) and the 3Dpol region (encoding the RNA polymerase) from 24 LV RNA-positive animals and a fragment of the 5′ untranslated region (UTR) sequence (used for defining strains) in sympatric small mammals. We define three new VP1 genotypes: two in bank voles (Myodes glareolus) (genotype 8 from Finland, Sweden, France, and Italy, and genotype 9 from France and Italy) and one in field voles (Microtus arvalis) (genotype 7 from Finland). There are several other indications that LV variants are host-specific, at least in parts of their range. Our results suggest that LV evolution is rapid, ongoing and affected by genetic drift, purifying selection, spillover and host evolutionary history. Although recent studies suggest that LV does not have zoonotic potential, its widespread geographical and host distribution in natural populations of well-characterized small mammals could make it useful as a model for studying RNA virus evolution and transmission

Peri-operative red blood cell transfusion in neonates and infants: NEonate and Children audiT of Anaesthesia pRactice IN Europe: A prospective European multicentre observational study

BACKGROUND: Little is known about current clinical practice concerning peri-operative red blood cell transfusion in neonates and small infants. Guidelines suggest transfusions based on haemoglobin thresholds ranging from 8.5 to 12 g dl-1, distinguishing between children from birth to day 7 (week 1), from day 8 to day 14 (week 2) or from day 15 (≥week 3) onwards. OBJECTIVE: To observe peri-operative red blood cell transfusion practice according to guidelines in relation to patient outcome. DESIGN: A multicentre observational study. SETTING: The NEonate-Children sTudy of Anaesthesia pRactice IN Europe (NECTARINE) trial recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. PATIENTS: The data included 5609 patients undergoing 6542 procedures. Inclusion criteria was a peri-operative red blood cell transfusion. MAIN OUTCOME MEASURES: The primary endpoint was the haemoglobin level triggering a transfusion for neonates in week 1, week 2 and week 3. Secondary endpoints were transfusion volumes, 'delta haemoglobin' (preprocedure - transfusion-triggering) and 30-day and 90-day morbidity and mortality. RESULTS: Peri-operative red blood cell transfusions were recorded during 447 procedures (6.9%). The median haemoglobin levels triggering a transfusion were 9.6 [IQR 8.7 to 10.9] g dl-1 for neonates in week 1, 9.6 [7.7 to 10.4] g dl-1 in week 2 and 8.0 [7.3 to 9.0] g dl-1 in week 3. The median transfusion volume was 17.1 [11.1 to 26.4] ml kg-1 with a median delta haemoglobin of 1.8 [0.0 to 3.6] g dl-1. Thirty-day morbidity was 47.8% with an overall mortality of 11.3%. CONCLUSIONS: Results indicate lower transfusion-triggering haemoglobin thresholds in clinical practice than suggested by current guidelines. The high morbidity and mortality of this NECTARINE sub-cohort calls for investigative action and evidence-based guidelines addressing peri-operative red blood cell transfusions strategies. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02350348

The Impact of Fast Radiation on the Phylogeny of Bactrocera Fruit Flies as Revealed by Multiple Evolutionary Models and Mutation Rate-Calibrated Clock

Several true fruit flies (Tephritidae) cause major damage to agriculture worldwide. Among them, species of the genus Bactrocera are extensively studied to understand the traits associated with their invasiveness and ecology. Comparative approaches based on a reliable phylogenetic framework are particularly effective, but several nodes of the Bactrocera phylogeny are still controversial, especially concerning the reciprocal affinities of the two major pests B. dorsalis and B. tryoni. Here, we analyzed a newly assembled genomic-scaled dataset using different models of evolution to infer a phylogenomic backbone of ten representative Bactrocera species and two outgroups. We further provide the first genome-scaled inference of their divergence by calibrating the clock using fossil records and the spontaneous mutation rate. The results reveal a closer relationship of B. dorsalis with B. latifrons than to B. tryoni, contrary to what was previously supported by mitochondrial-based phylogenies. By employing coalescent-aware and heterogeneous evolutionary models, we show that this incongruence likely derives from a hitherto undetected systematic error, exacerbated by incomplete lineage sorting and possibly hybridization. This agrees with our clock analysis, which supports a rapid and recent radiation of the clade to which B. dorsalis, B. latifrons and B. tryoni belong. These results provide a new picture of Bactrocera phylogeny that can serve as the basis for future comparative analyses

Pediatric anesthesia practice in Italy: a multicenter national prospective observational study derived from the Apricot trial

Pediatric anesthesia nowadays requires specific knowledge and expertise. The Anaesthesia PRactice In Children Observational Trial (APRICOT) was a European multicentre study designed for the identification of perioperative severe critical events and management. We aimed at analysing the Italian database in an attempt to determine the practice of anesthesia and the incidence of severe critical events in Italy

A comprehensive approach to the prevention of central venous catheter complications: results of 10-year prospective surveillance in pediatric hematology-oncology patients

none6noWe report our decennial experience with 1161 newly-placed long-term central venous catheters inserted in 919 hematology-oncology patients for a total of 413,901 CVC-days of observation. Most of the CVCs were partially-implanted, open-ended, Broviac-Hickman type of CVC (95 %). One thousand and twenty-four complications were recorded equal to 2.47 per 1000 CVC-days. The frequency of complications per CVC, the rate of episodes per 1000 CVC-days, and removal rate were malfunction/occlusion 42 %, 1.18/1000, and 2.3 %; mechanical (dislodgement/rupture/kinking) 18.3 %, 0.51/1000, and 77.4 %; bacteremia 14.8 %, 0.42/1000, and 18.6 %; exit-site/tunnel infection 11.5 %, 0.32/1000, and 9.7 %; thrombosis 0.86 %, 0.02/1000, and 30 %; pneumothorax 0.52 %, 0.01/1000, and 0. In multivariate analysis, the risk factors were for mechanical complications, a younger age <6.1 years at CVC insertion (HR 1.8, p = 0.0006); for bacteremia, a double lumen CVC (HR 3.1, p < 0.0001) and the surgical modality of CVC insertion (HR 1.5, p = 0.03); for exit-site/tunnel infection, a double lumen CVC (HR 2.1, p = 0.0003) and a diagnosis of leukemia or lymphoma (HR 1.8, p = 0.01); for malfunction/occlusion, an age <6.1 years (HR 1.6, p = 0.0003), the diagnosis of leukemia or lymphoma (HR 1.9, p < 0.0001) and double lumen CVC (HR 1.33, p = 0.023). The cumulative incidence of premature CVC removal was 29.2 % and the risk factors associated with this event were the surgical modality of CVC insertion (HR 1.4, p = 0.0153) and an age at CVC positioning less than 6.1 years (HR 1.6, p = 0.0025). We conclude that a best-practice set of rules resulted in reduced CVC complications.noneCesaro, Simone; Cavaliere, Mara; Pegoraro, Anna; Gamba, Piergiorgio; Zadra, Nicola; Tridello, GloriaCesaro, Simone; Cavaliere, Mara; Pegoraro, Anna; Gamba, Piergiorgio; Zadra, Nicola; Tridello, Glori