Animal development is classified as conditional or autonomous based on whether cell fates are specified through inductive signals or maternal determinants, respectively. Yet how these two major ...developmental modes evolved remains unclear. During spiral cleavage-a stereotypic embryogenesis ancestral to 15 invertebrate groups, including molluscs and annelids-most lineages specify cell fates conditionally, while some define the primary axial fates autonomously. To identify the mechanisms driving this change, we study Owenia fusiformis, an early-branching, conditional annelid. In Owenia, ERK1/2-mediated FGF receptor signalling specifies the endomesodermal progenitor. This cell likely acts as an organiser, inducing mesodermal and posterodorsal fates in neighbouring cells and repressing anteriorising signals. The organising role of ERK1/2 in Owenia is shared with molluscs, but not with autonomous annelids. Together, these findings suggest that conditional specification of an ERK1/2
embryonic organiser is ancestral in spiral cleavage and was repeatedly lost in annelid lineages with autonomous development.
Current evidence demonstrates the presence and persistence of microplastics in the marine food web. Seabirds are predators in marine ecosystems and are highly exposed to marine plastic debris through ...the food. The aim of this work was to examine the presence of microplastics in a long-distance migratory seabird, the Common tern (Sterna hirundo) (n = 10), and in their prey (n = 53) during the non-breeding season. The study was conducted in Punta Rasa, Bahía Samborombón, province of Buenos Aires, which is an important resting and feeding location for migratory seabirds and shorebirds in South America. Microplastics were found in all the birds examined. The occurrence of microplastics in the gastrointestinal tract (GIT) of Common terns (n = 82) was higher than in regurgitated prey (RP) (n = 28), which is likely reflecting trophic transfer process. Almost all microplastics found were fibers and only 3 were fragments. Microplastics were sorted by color; transparent, black and blue-colored fibers were the most abundant plastic types. Characterization of the polymer type by Fourier Transform Infrared Spectrometry (FTIR) revealed that cellulose ester plastics, polyethylene terephtalate, polyacrylonitrile and polypropylene were the most abundant types found in both the gastrointestinal tract and prey. Our results highlight the high levels of ingested microplastics in Common terns and in their prey, and reflect a concern in this important location for migratory seabirds.
Display omitted
•Microplastics were found in gastrointestinal tract from all the examined birds.•The microplastics found were almost fibers.•The abundance of microplastics was higher in birds than in their prey.•Microplastic differences between birds and prey reflect trophic transfer process.
•The influence of soil:lime dosage on the density and ultrasonic pulse velocity of rammed earth test tubes was analyzed.•The fracture energy and tensile strength values are related to the soil:lime ...dosage of the specimens.•Rammed earth could be considered as a quasi-brittle material that follows Hillerborg's discrete crack model.
Rammed earth is the construction system of many heritage structures and buildings in different regions of the planet, some of which are seismically active areas. For this reason, these historic buildings can sustain structural damage or have already been subjected to stresses that have led to high levels of cracking in the rammed earth walls. Therefore, knowledge of the fracture behavior of this material is essential to assess the actual state of structural safety and the remaining mechanical capacity. The number of studies on the fracture behavior of rammed earth is limited, and even fewer studies have considered lime as a stabilizer and used traditional materials. This study measured the density, ultrasonic pulse velocity, fracture energy and tensile strength of prismatic specimens with two different soil:lime dosages and found relationships between the different parameters analyzed and the dosages used. Finally, it was verified that the fracture behavior of rammed earth can be assumed to be similar to that of mass concrete from a qualitative standpoint. For this reason, rammed earth could be considered as a quasi-brittle material that follows Hillerborg’s discrete crack model.
Surface layers at the cathode-electrolyte interface strongly affect the performance of the Li-ion cell. Such surface layers are found during manufacturing and operation of the battery. As water can ...never be fully excluded from the manufacturing chain, it will form an additional surface layer situated between cathode and electrolyte. In this contribution, we investigate the interaction between the LiCoO2 electrode and H2O by a surface science approach. H2O was adsorbed stepwise onto a LiCoO2 thin film, and intermediate X-ray photoelectron spectroscopy analysis was performed after every step. Adsorption results in the formation of a Li2O/LiOH-type reaction layer on top of the electrode and downward band bending attributed to a Li+-ion transfer out of the electrode.
This study performs an analysis that will enable the evaluation of the quality, durability, and structure of repaired cartilaginous extracellular matrix tissue using an autologous-based particulated ...autograft cartilage and platelet-rich plasma treatment (PACI + PRP). A single-blind controlled experiment was conducted on 28 sheep to evaluate the efficacy of the PACI + PRP treatment for cartilage defects. Full-thickness 8 mm diameter defects were created in the weight-bearing area of both knees. The right knees received PACI + PRP. The left knees were treated with Ringer’s lactate solution (RLS) or hyaluronic acid (HA) injections. Sheep were euthanized at 9- or 18-months post-surgery. An extensive immunohistochemical analysis was performed to assess collagen types (I, II, III, V, VI, IX, X, XI) and aggrecan positivity. A semiquantitative scoring system provided a detailed evaluation of immunostaining. Collagens and aggrecan scores in the PACI + PRP groups were similar to healthy cartilage. Significant differences were found in collagens associated with matrix maturity (II and V), degradation (IX), structure and mechanics (VI), and hypertrophy (X) between healthy cartilage and RLS- or HA-repaired cartilage. The PACI + PRP treatment advanced the repair cartilage process in chondral defects with mature hyaline cartilage and enhanced the structural and mechanical qualities with better consistent cartilage, less susceptible to degradation and without hypertrophic formation over time.
The aim of this study was to evaluate the use of serum type II collagen cleavage epitope and serum hyaluronic acid as biomarkers for treatment monitoring in osteoarthritic dogs. For this purpose, a ...treatment model based on mesenchymal stem cells derived from adipose tissue combined with plasma rich in growth factors was used. This clinical study included 10 dogs with hip osteoarthritis. Both analytes were measured in serum at baseline, just before applying the treatment, and 1, 3, and 6 months after treatment. These results were compared with those obtained from force plate analysis using the same animals during the same study period. Levels of type II collagen cleavage epitope decreased and those of hyaluronic acid increased with clinical improvement objectively verified via force plate analysis, suggesting these two biomarkers could be effective as indicators of clinical development of joint disease in dogs.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Leptospirosis is a worldwide prevalent zoonosis and chronic kidney disease (CKD) is a leading global disease burden. Because of pathophysiological changes in the kidney, it has been suggested that ...these conditions may be associated. However, the extent of this interaction has not been synthetized. We aimed to systematically review and critically appraise the evidence on the association between leptospirosis and CKD.
Observational studies with a control group were selected. Leptospirosis, confirmed with laboratory methods, and CKD also based on a laboratory assessment, were the exposures and outcomes of interest. The search was conducted in EMBASE, MEDLINE, Global Health, Scopus and Web of Science. Studies selected for qualitative synthesis were assessed for risk of bias following the Newcastle-Ottawa Scale. 5,981 reports were screened, and 2 (n = 3,534) were included for qualitative synthesis. The studies were conducted in Taiwan and Nicaragua; these reported cross-sectional and longitudinal estimates. In the general population, the mean estimated glomerular filtration rate (eGFR) was lower (p<0.001) in people testing positive for antileptospira antibodies (eGFR = 98.3) than in negative controls (eGFR = 100.8). Among sugarcane applicants with high creatinine, those who were seropositive had lower eGFR (mean difference: -10.08). In a prospective analysis, people with high antileptospira antibodies titer at baseline and follow-up, had worse eGFR (p<0.05).
Although the available evidence suggests there may be a positive association between leptospirosis and CKD, whereby leptospirosis could be a risk factor for CKD, it is still premature to draw conclusions. There is an urgent need for research on this association.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
PDF
