Doppler velocimetry of the uterine and umbilical arteries is used to predict preeclampsia and monitor fetal outcomes. There have been no reports of Doppler velocimetry indices in pregnancies ...conceived after uterus transplantation, which differ from traditional pregnancies because of different uterine vascular inflow and outflow and exposure to immunosuppressive agents. We sought to examine whether Doppler indices can be used to predict embryo transfer success after uterus transplantation and whether Doppler indices across pregnancy predict fetal growth restriction.
This was a single-center cohort observational study of 14 uterus transplant recipients who underwent embryo transfer. Of these, 12 women successfully delivered 14 babies. Five Doppler investigations were performed within the cohort: (1) prepregnancy; (2) uterine artery assessment across pregnancy; (3) umbilical artery assessment across pregnancy; (4) successive pregnancies; and (5) fetal growth.
Prepregnancy uterine artery Doppler indices did not correlate with successful implantation after embryo transfer. Uterine artery Doppler indices in uterus transplant recipients decreased across pregnancy as described in pregnancies without uterus transplantation. The umbilical artery systolic/diastolic velocity ratio was lower at all weeks of gestation after uterus transplantation compared with values described in pregnancies without uterus transplantation. In those women who delivered two successive babies after uterus transplant, umbilical artery Doppler indices were significantly lower during the second pregnancy. There was always forward flow throughout diastole in the umbilical arteries, and no babies experienced fetal growth restriction.
In our study, uterus transplantation was not associated with abnormal blood flow indices in either the uterine or umbilical arteries. Although Doppler indices were not predictive of embryo transfer success, they supported the expectation that pregnancies after uterus transplantation at our center result in normally grown babies.
· Uterus transplantation is not associated with abnormal blood flow indices.. · Prepregnancy uterine artery Doppler indices did not correlate with successful embryo implantation.. · Doppler assessment supports the expectation of normal placentation, fetal growth, and healthy live births after uterus transplantation..
Like many jurisdictions across North America, the province of Nova Scotia (NS) is faced with the challenge of restoring its forests to a more natural, presettlement state through implementation of ...ecological forestry. At the core of ecological forestry is the idea that natural forest structures and processes may be approximated by designing management practices that emulate natural disturbances. Successful natural disturbance emulation depends on fundamental knowledge of disturbance characteristics, including identification of specific disturbance agents, their spatial extent, severity, and return interval. To date, no comprehensive synthesis of existing data has been undertaken to document the natural disturbance regime of NS forests, limiting the application of natural disturbance emulation. Using over 300 years of documents and available data, we identified the main natural disturbance agents that affect NS forests and characterized their regimes. Overall, fire, wind (predominantly hurricanes), and outbreaks of spruce budworm (Choristoneura fumiferana (Clemens)) are the most important disturbance agents, causing substantial areas of low– (<30% mortality), moderate– (30%–60%), and high– (>60%) severity disturbance. While characterization of natural historic fire is challenging, due to past human ignitions and suppression, we estimated that the mean annual disturbance rate of moderate– to high-severity fire ranged between 0.17% and 0.4%·year−1 (return interval of 250–600 years), depending on ecosystem type. Hurricanes make landfall in NS, on average, every 7 years, resulting in wide-scale (>500 ha) forest damage. While hurricane track and damage severity vary widely among storms, the return interval of low– to high-severity damage is 700–1250 years (0.14%–0.08%·year−1). Conversely, the return interval of host-specific spruce budworm outbreaks is much shorter (<50 years) but more periodic, causing wide-scale, low– to high-severity damage to spruce–fir forests every 30–40 years. Further disturbance agents such as other insects (e.g., spruce beetle), diseases, ice storms, drought, and mammals can be locally important and (or) detrimental to individual tree species but contribute little to overall disturbance in NS. Climate change is expected to significantly alter the disturbance regime of NS, affecting current disturbances (e.g., increased fire) and driving the introduction of novel agents (e.g., hemlock wooly adelgid), and continued monitoring is needed to understand these changes.
Comme de nombreuses autorites a travers l’Amerique du Nord, la province de Nouvelle-Ecosse (N.-E.) est confrontee au defi de restaurer ses forets dans un etat plus naturel, anterieur a la colonisation, par la mise en oeuvre de la foresterie ecologique. Au coeur de la foresterie ecologique se trouve l’idee que l’on peut se rapprocher des structures et les processus forestiers naturels en concevant des pratiques de gestion qui imitent les perturbations naturelles. L'emulation reussie des perturbations naturelles depend de la connaissance fondamentale que l’on a des caracteristiques de ces perturbations, y compris l’identification d’agents specifiques de perturbation, leur etendue spatiale, leur gravite et leur intervalle de retour. A ce jour, aucune synthese approfondie des donnees existantes n’a ete entreprise pour documenter le regime de perturbations des forets de N.-E., ce qui limite l’application de l’emulation des perturbations naturelles. En utilisant des documents et des donnees disponibles couvrant une periode de 300 ans, les auteurs ont identifie les principaux agents de perturbation naturelle qui affectent les forets de N.-E. et caracterise leurs regimes. Dans l’ensemble, le feu, le vent (principalement les ouragans) et les eclosions de tordeuses des bourgeons de l’epinette (TBS; Choristoneura fumiferana (Clemens)) constituent les principaux agents de perturbation, produisant des zones considerables de perturbations de severite faible (<30 % de mortalite), moderee (30–60 %) et elevee (>60 %). Bien que la caracterisation des feux historiques naturels soit difficile, en raison des allumages et des suppressions d’origine humaine passes, les auteurs estiment que le taux de perturbation annuel des feux de gravite moderee a elevee se situait entre 0,17 et 0,4 %・an−1 (intervalle de retour de 250 a 600 ans), selon le type d’ecosysteme. Les ouragans touchent terre en N.-E. en moyenne tous les 7 ans, entrainant des dommages forestiers a grande echelle (>500 ha). Bien que la trajectoire d’un ouragan etla severite des dommages varient grandement d’une tempete a l’autre, l’intervalle de retour des dommages de severite faible a elevee est de 700 a 1250 ans (0,14 a 0,08・an−1). A l’inverse, l’intervalle de retour d’eclosions de TBE specifiques a l’hote est beaucoup plus court (<50 ans), mais plus periodique, provoquant des dommages a grande echelle de severite faible a elevee aux forets de coniferes tous les 30 a 40 ans. D’autres agents de perturbation tels que d’autres insectes (p. ex. le dendroctone de l’epinette), des maladies, des tempetes de verglas, la secheresse ou des mammiferes peuvent etre importants ou nuisibles a l’echelle locale pour des especes d’arbres particulieres, mais ils contribuent peu a la perturbation globale en N.-E. On s’attend a ce que les changements climatiques modifient de maniere significative le regime des perturbations en N.-E., en affectant les perturbations actuelles (p. ex. l’accroissement des incendies) et en facilitant l’introduction de nouveaux agents (p. ex. le puceron lanigere de la pruche), et une surveillance continue est necessaire pour comprendre ces changements.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Historically, the role of aggression in the social lives of animals overwhelmingly focused on males. In recent years, however, female-female aggression in vertebrates, particularly lizards, has ...received increasing attention. This growing body of literature shows both similarities and differences to aggressive behaviours between males. Here, we document female-female aggression in captive Gila monsters (
). Based on four unique dyadic trials (eight adult female subjects), we developed a qualitative ethogram. Unexpected and most intriguing were the prevalence and intensity of aggressive acts that included brief and sustained biting, envenomation, and lateral rotation (i.e. rolling of body while holding onto opponent with closed jaws). Given specific behavioural acts (i.e. biting) and the results of bite-force experiments, we postulate that osteoderms (bony deposits in the skin) offer some degree of protection and reduce the likelihood of serious injury during female-female fights. Male-male contests in
in contrast, are more ritualized, and biting is rarely reported. Female-female aggression in other lizards has a role in territoriality, courtship tactics, and nest and offspring guarding. Future behavioural research on aggression in female Gila monsters is warranted to test these and other hypotheses in the laboratory and field.
A common feature in patients with abdominal aortic aneurysms (AAA) is the formation of a nonocclusive intraluminal thrombus (ILT) in regions of aortic dilation. Platelets are known to maintain ...hemostasis and propagate thrombosis through several redundant activation mechanisms, yet the role of platelet activation in the pathogenesis of AAA associated ILT is still poorly understood. Thus, we sought to investigate how platelet activation impacts the pathogenesis of AAA. Using RNA-sequencing, we identify that the platelet-associated transcripts are significantly enriched in the ILT compared to the adjacent aneurysm wall and healthy control aortas. We found that the platelet specific receptor glycoprotein VI (GPVI) is among the top enriched genes in AAA ILT and is increased on the platelet surface of AAA patients. Examination of a specific indicator of platelet activity, soluble GPVI (sGPVI), in two independent AAA patient cohorts is highly predictive of a AAA diagnosis and associates more strongly with aneurysm growth rate when compared to D-dimer in humans. Finally, intervention with the anti-GPVI antibody (JAQ1) in mice with established aneurysms blunted the progression of AAA in two independent mouse models. In conclusion, we show that levels of sGPVI in humans can predict a diagnosis of AAA and AAA growth rate, which may be critical in the identification of high-risk patients. We also identify GPVI as a novel platelet-specific AAA therapeutic target, with minimal risk of adverse bleeding complications, where none currently exist.
Climate change will drive significant changes in vegetation cover and also impact efforts to restore ecosystems that have been disturbed by human activities. Bitumen mining in the Alberta oil sands ...region of western Canada requires reclamation to “equivalent land capability,” implying establishment of vegetation similar to undisturbed boreal ecosystems. However, there is consensus that this region will be exposed to relatively severe climate warming, causing increased occurrence of drought and wildfire, which threaten the persistence of both natural and reclaimed ecosystems. We used a landscape model, LANDIS‐II, to simulate plant responses to climate change and disturbances, forecasting changes to boreal forests within the oil sands region. Under the most severe climate forcing scenarios (representative concentration pathway RCP 8.5) the model projected substantial decreases in forest biomass, with the future forest being dominated by drought‐ and fire‐tolerant species characteristic of parkland or prairie ecosystems. In contrast, less extreme climate forcing scenarios (RCPs 2.6 and 4.5) had relatively minor effects on forest composition and biomass with boreal conifers continuing to dominate the landscape. If the climate continues to change along a trajectory similar to those simulated by climate models for the RCP 8.5 forcing scenario, current reclamation goals to reestablish spruce‐dominated boreal forest will likely be difficult to achieve. Results from scenario modeling studies such as ours, and continued monitoring of change in the boreal forest, will help inform reclamation practices, which could include establishment of species better adapted to warmer and drier conditions.
A simple, modified Metal-Organic Chemical Deposition (MOCD) method for Pt, PtRu and PtCo nanoparticle deposition onto a variety of support materials, including C, SiC, B
4
C, LaB
6
, TiB
2
, TiN and ...a ceramic/carbon nanofiber, is described. Pt deposition using Pt(acac)
2
as a precursor is shown to occur
via
a mixed solid/liquid/vapour precursor phase which results in a high Pt yield of 90-92% on the support material. Pt and Pt alloy nanoparticles range 1.5-6.2 nm, and are well dispersed on all support materials, in a one-step method, with a total catalyst preparation time of ∼10 hours (2.4-4× quicker than conventional methods). The MOCD preparation method includes moderate temperatures of 350 °C in a tubular furnace with an inert gas supply at 2 bar, a high pressure (2-4 bar) compared to typical MOCVD methods (∼0.02-10 mbar). Pt/C catalysts with Pt loadings of 20, 40 and 60 wt% were synthesised, physically characterised, electrochemically characterised and compared to commercial Pt/C catalysts. TEM, XRD and
ex situ
EXAFS show similar Pt particle sizes and Pt particle shape identifiers, namely the ratio of the third to first Pt coordination numbers modelled from
ex situ
EXAFS, between the MOCD prepared catalysts and commercial catalysts. Moreover, electrochemical characterisation of the Pt/C MOCD catalysts obtained ORR mass activities with a maximum of 428 A g
Pt
−1
at 0.9 V, which has similar mass activities to the commercial catalysts (80-160% compared to the commercial Pt/C catalysts).
A simple, modified Metal-Organic Chemical Deposition (MOCD) method for Pt, PtRu and PtCo nanoparticle deposition onto a variety of support materials, including C, SiC, B
4
C, LaB
6
, TiB
2
, TiN and a ceramic/carbon nanofiber, is described.
Despite the success of immune checkpoint blockade therapy, few strategies sufficiently overcome immunosuppression within the tumor microenvironment (TME). Targeting regulatory T cells (T
) is ...challenging, because perturbing intratumoral T
function must be specific enough to avoid systemic inflammatory side effects. Thus, no T
-targeted agents have proven both safe and efficacious in patients with cancer. Neuropilin-1 (NRP1) is recognized for its role in supporting intratumoral T
function while being dispensable for peripheral homeostasis. Nonetheless, little is known about the biology of human NRP1
T
and the signals that regulate NRP1 expression. Here, we report that NRP1 is preferentially expressed on intratumoral T
across six distinct cancer types compared to healthy donor peripheral blood peripheral blood lymphocyte (PBL) and site-matched, noncancer tissue. Furthermore, NRP1
T
prevalence is associated with reduced progression-free survival in head and neck cancer. Human NRP1
T
have broad activation programs and elevated suppressive function. Unlike mouse T
, we demonstrate that NRP1 identifies a transient activation state of human T
driven by continuous T cell receptor (TCR) signaling through the mitogen-activated protein kinase pathway and interleukin-2 exposure. The prevalence of NRP1
T
in patient PBL correlates with the intratumoral abundance of NRP1
T
and may indicate higher disease burden. These findings support further clinical evaluation of NRP1 as a suitable therapeutic target to enhance antitumor immunity by inhibiting T
function in the TME.
Predicting forest composition change through time is a key challenge in forest management. While multiple successional pathways are theorized for boreal forests, empirical evidence is lacking, ...largely because succession has been inferred from chronosequence and dendrochronological methods. We tested the hypotheses that stands of compositionally similar overstory may follow multiple successional pathways depending on time since last stand-replacing fire (TSF), edaphic conditions, and presence of intermediate disturbances. We used repeated measurements from combining sequential aerial photography and ground surveys for 361 boreal stands in central Canada. Stands were measured in 8-15 yr intervals over a ~60 yr period, covering a wide range of initial stand conditions. Multinomial logistic regression was used to analyze stand type transitions. With increasing TSF, stands dominated by shade-intolerant Pinus banksiana, Populus sp., and Betula papyrifera demonstrated multiple pathways to stands dominated by shade-tolerant Picea sp., Abies bahamea, and Thuja occidentalis. Their pathways seemed largely explained by neighborhood effects. Succession of stands dominated by shade-tolerant species, with an exception of stands dominated by Picea sp., was not related to TSF, but rather dependent on edaphic conditions and presence of intermediate disturbances. Varying edaphic conditions caused divergent pathways with resource limited sites being dominated by nutrient-poor tolerant species, and richer sites permitting invasion of early successional species and promoting species mixtures during succession. Intermediate disturbances promoted deciduous persistence and species diversity in A. balsamea and mixed-conifer stands, but no evidence was detected to support "disturbance accelerated succession". Our results demonstrate that in the prolonged absence of stand-replacing disturbance boreal forest stands undergo multiple succession pathways. These pathways are regulated by neighborhood effects, resource availability, and presence of intermediate disturbance, but the relative importance of these regulators depends on initial stand type. The observed divergence of successional pathways supports the resource-ratio hypothesis of plant succession.
Regulating levels of centromeric histone H3 (CenH3) variant is crucial for genome stability. Interaction of Psh1, an E3 ligase, with the C terminus of Cse4 has been shown to contribute to its ...proteolysis. Here, we demonstrate a role for ubiquitination of the N terminus of Cse4 in regulating Cse4 proteolysis for faithful chromosome segregation and a role for Doa1 in ubiquitination of Cse4.
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